AIRAH Application Manual
DA19 - HVAC&R Maintenance

Public Review Draft

This draft is open for industry/public review and comment from Monday 27^th August 2018 until 5pm Monday 17^th September 2018.

Comments are invited on the technical content, wording and general arrangement of the DA.

Where you consider that specific content is too simplistic, too complex or incorrect please suggest an alternative.  Please provide supporting reasons and suggested alternative wording for each comment.  Where appropriate, changes will be incorporated before the final manual is published.  If the draft is acceptable without change, an acknowledgment to this effect would be appreciated.

The draft is available in WORD and PDF formats. Comments may be submitted using WORD (track changes), PDF (comment facility) or separately from the document.  For separate comments please indicate relevant clause numbers for each comment in the following suggested format -

If you know of other persons or organisations that may wish to comment on this draft, please advise them of its availability.

Further copies of the draft are available for download from AIRAH www.airah.org.au

All comment should be submitted to phil.wilkinson@airah.org.au  before:

5pm Monday 17^th September 2018

HVAC&R Maintenance

Contents

1.      INTRODUCTION.. 5

1.1.       Introduction to DA19. 5

1.2.       Scope. 5

1.3.       Purpose. 7

1.4.       Application. 7

1.5.       Relationship of DA19 to current standards and codes. 8

2.      MAINTENANCE OVERVIEW... 9

2.1.       What is maintenance?. 9

2.2.       The benefits of maintenance. 10

2.3.       The risks of poor maintenance. 10

2.4.       The maintenance imperatives. 11

2.5.       Maintenance roles and responsibilities. 13

2.6.       Maintenance health and safety. 19

2.7.       Compliance with mandatory maintenance. 20

2.8.       Maintenance to protect the environment 24

2.9.       Life cycle costing. 25

2.10.         Plant service life. 25

2.11.         Maintenance and noise issues. 26

3.      MAINTENANCE IN DESIGN, INSTALLATION AND COMMISSIONING.. 28

3.1.       General 28

3.2.       Design considerations. 28

3.3.       Design checklist 29

3.4.       Safety provisions. 30

3.5.       Access for maintenance. 30

3.6.       Controls. 33

3.7.       Monitoring and metering. 34

3.8.       Refrigerant management 34

3.9.       Documentation. 35

3.10.         Water and drainage. 37

3.11.         Water treatment 37

3.12.         Power 38

3.13.         Commissioning. 38

3.14.         Plant performance and capacity testing. 38

3.15.         Defects liability period. 40

4.      MANAGING MAINTENANCE IN OPERATION.. 42

4.1.       General 42

4.2.       Maintenance specification. 42

4.3.       Maintenance performance standards. 43

4.4.       Maintenance planning. 47

4.5.       Maintenance program.. 47

4.6.       Maintenance implementation. 48

4.7.       Trouble shooting. 49

4.8.       Maintenance reporting. 50

4.9.       Maintenance monitoring and review.. 50

4.10.         Maintenance budgeting. 51

5.      MAINTENANCE STRATEGIES.. 57

5.1.       Maintenance strategies defined. 57

5.2.       Preventative Maintenance (PM) strategies. 57

5.3.       Predictive maintenance (PdM) strategies. 60

5.4.       Predictive Vs Preventative maintenance. 63

5.5.       Incorporating PdM into PM.. 64

5.6.       Reactive maintenance strategy. 64

5.7.       Good practice Vs best practice maintenance. 64

5.8.       Selecting a maintenance strategy. 66

5.9.       Risk assessment for strategy selection. 67

5.10.         Cost/benefit analysis in strategy selection. 69

5.11.         Maintenance delivery models. 69

5.12.         Maintenance records. 72

5.13.         Maintenance staff 72

5.14.         Maintenance staff safety. 73

6.      SMART MAINTENANCE.. 75

6.1.       Introduction. 75

6.2.       Standardising digital information. 75

6.3.       Digitisation of maintenance management 76

6.4.       Digitisation of maintenance delivery. 79

6.5.       Digitisation of Asset Management 82

6.6.       Protecting maintenance information and data. 83

6.7.       Monitoring and metering HVAC&R.. 84

6.8.       Automated fault detection and diagnosis systems. 88

6.9.       Condition Monitoring Systems. 89

6.10.         Digital predictive methodology limitations. 91

6.11.         New digital competencies. 91

6.12.         Smart Maintenance Implementation. 91

7.      CONTINUOUS IMPROVEMENT: Tuning and Optimisation. 94

7.1.       Surveys and audits. 94

7.2.       System optimisation procedures. 95

7.3.       Energy efficiency maintenance. 99

7.4.       Energy optimisation and HVAC&R.. 99

7.5.       Water conservation maintenance. 103

7.6.       Refrigeration system maintenance – AS/NZS 5149.4. 105

7.7.       Refrigerant management 106

7.8.       Indoor air quality maintenance. 107

7.9.       Performance based microbial control 107

7.10.         Incorrectly sized plant 109

7.11.         Refurbishments, replacements and upgrades. 110

Appendix A - HVAC&R maintenance schedules. 111

Appendix B - Preventative maintenance schedule example. 112

Appendix C - Operating and maintenance manuals. 113

Appendix D - Risk based maintenance. 116

Appendix E - Maintenance costs and reliability. 121

Appendix F - Glossary of terms. 129

Appendix G – Referenced documents. 133

INTRODUCTION

Introduction to DA19

Welcome to the AIRAH application manual on the maintenance of heating, ventilating, air conditioning and refrigeration (HVAC&R) systems.

Maintenance of HVAC&R services is carried out to reduce the occurrence of system failures, to optimise or retain the operating performance of the system and to extend plant service life. Some maintenance is required by legislation.

The link between maintenance practices and building or facility performance-in-use is direct and undeniable. Maintenance is necessary to ensure safety, reliability and comfort as well as to manage operational costs and environmental ratings.

The relative importance of these outcomes can only be prioritized by the maintenance client, the demand organisation which is typically the system owner, so the first step in developing a maintenance plan is for the owner to document the required performance outcomes of the maintenance activity.

This guideline describes the spectrum of maintenance activities that can then be planned and implemented to ensure the performance outcomes are achieved.  As with all successful management activities the maintenance plan should include periodic review with the intention of continuous improvement.

Maintenance must respond to the changing environment in which HVAC&R exists with changes in technology, expectations of new levels of environmental protection and heightened dependency of all sectors of the Australian economy on safe, reliable and effective HVAC&R systems.

Maintenance is purchased, delivered and executed in new and innovative ways. Modern maintenance practices are integral to the operation and success of buildings and businesses. Increased demand for better maintenance outcomes requires a better maintenance management model. Modern maintenance is developing into a partnership between the building owner, manager and/or tenant, and maintenance contractors.

This manual defines what maintenance is, why maintenance is performed and discusses the maintenance roles and responsibilities of the various supply chain stakeholders. The manual outlines how best to manage maintenance and defines a structured process for the development of a system of maintenance appropriate to a specific building or application.

Scope

The scope of this application manual includes the maintenance and maintenance management of heating, ventilation, air conditioning and refrigeration (HVAC&R) systems and services.

This manual does not contain maintenance information for other building services such as electrical distribution systems, lighting systems, lifts, fire detection and fire control or suppression systems.

The maintenance discussed in this manual can be applied to achieve a variety of objectives including:

• • Health and Safety
  • Legal compliance
  • Contractual compliance, including owner’s obligations to tenants and occupants
  • Comfort conditions
  • Indoor air quality
  • Reliability
  • Asset protection
  • Risk minimisation
  • Energy efficiency
  • Water conservation
  • Workplace productivity
  • Indoor Environmental Quality
  • Reduction in environmental impact
  • Achievement or retention of building ratings

The maintenance described in this manual is different to that obtained under warranty or during the defects liability period of a new building. Routine or preventative maintenance, in addition to that obtained under the installation contract, is required throughout the life of the plant to ensure it is kept in good operating condition and that the specified operating requirements are achieved.

Figure 1.1 provides a map outlining the scope and application of this manual.

Figure 1.1 MAP of application manual

Purpose

The focus of this manual is to assist in the development and review of the routine and preventative maintenance programs in use by building services engineers, maintenance engineers and plant engineers and to provide guidance in the preparation of maintenance contracts for HVAC&R building services. A further purpose is to provide a guide to the programming of the maintenance service required for items usually found in HVAC&R systems and where considered necessary, to explain how the maintenance work should be performed. Detailed maintenance schedules are included for common HVAC&R plant items and systems and guidance on how these schedules can be tailored to individual buildings and systems is included.

This manual incorporates a much more central focus on the role that HVAC&R maintenance can play in reducing environmental impacts or ecological footprints of buildings or processes. Reducing energy use, conserving water, managing refrigerants and water treatment chemicals are all issues directly linked to and addressed by HVAC&R maintenance. The sustainability implications of maintenance actions and choices are considered throughout the manual.

An important purpose of this manual is also to outline for the owner, the maintenance manager and the maintenance contractor, the extent of service required in order to maintain a system at peak efficiency at all times.  The manual outlines to the system owner/user the choices of the type of maintenance service that can be provided.

Application

This application manual discusses HVAC&R maintenance in detail and can be applied across the range of building stock and systems. It can be applied to large systems associated with commercial and industrial buildings and to smaller light commercial and residential systems. It can also be applied to systems associated with processes, such as refrigeration, rather than buildings.

This manual is not a maintenance specification. Maintenance specifications and programs need to be tailored specifically to a systems plant and operational requirements. This manual can be used to develop system specific maintenance programs and specifications. Appendix A provides a compilation of standard maintenance schedules for plant and equipment commonly found in HVAC&R applications. Appendix B illustrates a method of preparing a scheduled maintenance program for a system using the standard schedules of Appendix A.

The information in the manual is provided in a layered structure, starting with general information about maintenance and maintenance management, moving on to more detailed information on maintenance planning, maintenance delivery and maintenance review and leading to detailed technical maintenance instructions in the routine maintenance schedules. Much of the detailed technical resources such as maintenance schedules and audit procedures have been located in the Appendices.

This manual can be applied, in whole or in part, by building owners, building managers, facility managers, building tenants, building occupants, system designers, mechanical contractors, mechanical service providers, specialist service providers, service technicians, regulatory authorities or certifiers. Different users can access different levels of technical detail as appropriate to their needs.

Table 1.1 provides a guide to the relevance of the various sections and appendices of the guide where guide users and stakeholders in maintenance may find the most relevant information to their fields of interest.

Table 1.1       APPLICATION OF DA19

This document is a guide only and does not replace the specific requirements of any legislation, regulations, codes or standards that are in force within the jurisdiction of the system or the requirements of a manufacturer, particularly in regard to warranty or guarantee conditions.

Relationship of DA19 to current standards and codes

Users of this application manual should note that DA19 has been developed as a guideline document, not a standard and not a regulatory requirement.

The maintenance schedules provided in this manual are intended to represent industry good or best practice in relation to the application and delivery of preventative maintenance programs targeting a minimum regulatory compliance standard and, depending on the objectives for the plant or building, industry good or best maintenance practice.

Where there is a conflict between this guideline and a minimum regulatory compliance Australian Standard or regulatory document it is the Standard/Regulation that takes precedence and should be followed for compliance to be claimed, not this guideline.

MAINTENANCE OVERVIEW

What is maintenance?

Maintenance covers all the activities that are carried out on plant and equipment in order to retain performance and provide assurance that systems will work as required when required. The maintenance activities include all technical, administrative, managerial, monitoring and supervisory activities. Maintenance is planning and scheduling, monitoring and reviewing. Maintenance is not just fixing equipment after a failure but also performing routine, preventative actions that keep a device or system in working order and prevent future operational issues from arising.

Figure 2.1 Aspects of maintenance

The bulk of maintenance activities occur in the operational phase of the life cycle of a HVAC&R system. However, maintenance should be considered and accommodated throughout all phases of the system lifecycle, including concept, design, construction, commissioning and operation.

Figure 2.2 Lifecycle of a HVAC&R system

The benefits of maintenance

The most important things for an owner to understand are the benefits that flow from an investment in HVAC&R maintenance. Before deciding on the maintenance approach to take, and there are many options with a range of investment requirements and potential outcomes, the benefits of maintenance should be understood. Good maintenance can provide:

• Compliance with legal requirements, demonstrating that systems are safe and available, and regulatory duties are met – compliance with regulatory duties are not optional and maintenance delivery provides a framework for owners to provide verification that duties have been met.
• Provision of desired service levels for availability, comfort and productivity – maintained plant operates better and more reliably
• Operation at lowest life cycle cost, operating efficiently and maintained so that desired equipment lifetimes are achieved or exceeded

A good maintenance program will ensure that the maintenance investment is matched by performance to the requirements.

Conversely, poor maintenance can lead to inefficient systems that break down regularly, rarely achieve performance standards and need to be replaced before expected.

The risks of poor maintenance

Poor maintenance of HVAC&R plant and systems will result in unsatisfactory operation, higher costs, unnecessary unexpected breakdowns and can expose system owners and operators to considerable cost and risk. Compliance with regulated requirements may not be met and tenant requirements or contractual obligations may not be achieved.

There is never an appropriate time for a system to fail. Breakdowns which occur from a lack of maintenance are often critical or severe in nature, resulting in higher repair costs and longer term service deprivation.  Breakdown failures can have a cascade effect and cause damage to other related plant items or processes.

Poor maintenance will usually result in the plant becoming less efficient, with higher operating costs, while the required operating conditions may not be achieved. Risks to building owners, operators, managers and occupants will all increase.

Indoor air quality and indoor environment quality are often impacted by poor maintenance, due to issues such as reduced outdoor air quantities, increased noise and vibration, or poor HVAC hygiene. Any energy or water conservation measures built into the system can also rapidly degrade if not maintained.

Poor maintenance can affect the market valuation and market position of a building asset and the future costs of poor maintenance can include:

• Increased consumption of electricity, water, refrigerant
• Premature failure of systems and components
• Loss of functionality of the building, facility or process
• Reduction in asset value
• Increased costs of repairs

All maintenance generates economic benefit and there are a range of other imperatives that drive maintenance delivery.

The maintenance imperatives

The three basic reasons why proper maintenance of HVAC&R plant is necessary are:

Safety, health, and environment - to ensure health and safety and to protect the environment, maintenance may be as required by law or be conducted in response to risk assessments.

Performance commitments -  to enable productivity of occupants through effective comfort control, and retaining environmental ratings in energy, emissions and water.

Economic efficiency -  to reduce system lifetime costs including operational costs, replacement costs, and, for the owner, potential leasing penalties should systems not meet specified conditions.

Different emphasis may be placed on each of these imperatives depending on the owner, the user, or the use to which the system or building is put.

Safety, health, and environment

Compliance with the law, and the associated statutory regulations applying to a particular building or facility, is the minimum maintenance requirement to be satisfied.  There are specific laws relating to building systems maintenance and more general laws concerned with occupant health and safety and environmental safety.

Public Health and Safety

In many Australian jurisdictions there are specific regulatory requirements relating to Public Health and Safety including the maintenance of fire and smoke control systems, cooling water systems, fire safety aspects of air handling systems, and other building services systems that impact occupant health and safety (fire alarms, sprinkler systems and the like).

These regulations often include mandatory compliance statements or certification requirements.  There is also the more general regulatory requirement that any health and safety related equipment, that is required to have a particular performance at the time of installation/building approval, must maintain that required performance for its operational life.

Building owners and managers should ensure that they are fully aware of all of their legal duties, within the jurisdiction in which they operate.

Work Health and Safety

State and Territory Work Health and Safety (WHS) and Occupational Health and Safety (OH&S) laws and regulations outline a range of duties that designers, installers, service providers, owners and persons conducting a business or undertaking (PCBU) have in relation to maintenance:

• Designers must consider the safety implications of the designs they conceive, in relation to the future provision of maintenance so that the safety risks for installers, operators and maintenance service providers are minimised as far as is reasonably practicable – this duty is known as safety-in-design
• Installers must deliver on the safety-in-design intent, to minimise the safety risks, and this includes identifying and resolving any safety risks that have not been mitigated by the designer.
• Service providers must ensure that maintenance work procedures are safe and effective, generally in accordance with the manufacturer or supplier instructions
• Building owners and facility managers must provide safe access to plant for maintenance and facilitate the delivery of maintenance to systems that contribute or affect occupant health and safety. They have a duty to ensure any foreseeable risks to workers or occupants are mitigated as far as is reasonably practicable
• PCBUs must ensure that systems contributing to health and safety are maintained and that the maintenance delivery procedures and outcomes are safe. HVAC&R systems and plantrooms are workplaces for maintenance service personnel.

Designers, manufacturers, installers, constructors, importers and suppliers of plant, structures or substances can influence the safety of these products before they are used in the workplace.  These people are required to ensure, so far as is reasonably practicable, that products are made without risks to the health and safety of the people who use them ‘downstream’ in the product lifecycle, i.e. during inspection, storage, operation, cleaning, maintenance or repair. This importantly includes the provision of information in relation to the safe use of the product or plant.

It is important to demonstrate that any mandatory inspection and testing regime is properly managed and that the results are being recorded, reported and acted upon. Records are often required to be kept to verify that required maintenance has been carried out and demonstrate compliance with legal and regulatory requirements.

As well as these specific legal considerations there are those of common law liability, duty of care and due diligence as they relate to the conditions of insurance. Local council regulations including special local planning conditions and food services regulations can also impact HVAC&R maintenance.

In addition, the maintenance of refrigeration systems containing synthetic refrigerants is also subject to specific environmental regulation.

Protecting the environment

HVAC&R systems can cause adverse environmental impact, particularly in relation to impacts from refrigerants, environmental noise, energy use, and indoor air quality issues deriving from poor building ventilation standards or HVAC hygiene. These environmental impacts relate, both to the size and diversified nature of the industry, and to the fact that HVAC&R technology is fundamental to, and intrinsic in, almost all aspects of modern Australian life

There are several environmental regulatory drivers for maintenance delivery and these include refrigerant management regulation and environmental noise control.

The Ozone Protection and Synthetic Greenhouse Gas Management Act 1989 and related Acts (the OSGG Acts) protect the environment by reducing emissions of ozone depleting substances (ODS) and synthetic greenhouse gases (SGGs). These national regulations apply to all people who acquire, possess, dispose of or handle ODSs or SGGs in the refrigeration and air conditioning industry.

Environmental noise regulations are generally developed by state government and enforced by local council. HVAC&R noise is typically the most problematic in high density residential situations. Noise limits are generally specified for both daytime and night time and where a plant exceeds the limits specified it may be restricted from operating.  Regulatory responsibility for HVAC&R noise levels generally rests with the plant owner.

Performance commitments

There is increasing empirical evidence around the connection between the quality of the indoor environment quality (IEQ) and the productivity of a workplace.

Ventilation rates, thermal comfort, outdoor airflows, humidity ranges, noise, air movement, air distribution arrangements and operator control all have a direct effect on IEQ. Effective maintenance of HVAC&R systems plays an important role in ensuring that these aspects are addressed.

Responsiveness or response times to attendance and rectification of reported problems have also been shown to contribute to occupant satisfaction or dissatisfaction.

Similarly, sustainability goals such as water conservation and indoor air quality can be enhanced by maintenance goals and activities. Building performance rating schemes such as Green Star Performance and National Australian Built Environment Rating System (NABERS) are non-regulatory schemes increasingly being adopted by the property market, government agencies and discerning tenants as the measure of a buildings’ sustainability and environmental performance. The role of HVAC&R systems maintenance is crucial in achieving these ratings and more importantly in retaining or improving them.

Economic efficiency

The HVAC&R services within a building form an asset base that will depreciate over time and with use. This depreciation in value will accelerate if there is system misuse or inadequate maintenance and should decelerate when increased levels of maintenance or condition monitoring are applied.

Economic considerations for maintenance also extend to minimising ongoing plant operating and capital costs and the work associated with ensuring that the optimum energy efficiency is obtained from the plant and that the optimum economic plant life is also achieved.

For existing HVAC&R systems the potential to generate economic savings by the application of maintenance for energy efficiency and water conservation is high.  The costs and savings of alternative or competing maintenance plans can be analysed and economic considerations can have a significant impact on maintenance decisions and planning.

From an economic point of view, it is also possible to utilise risk analysis to determine the likely financial implications to a business should a breakdown or plant failure occur that results in the owner being at risk of tenant/occupant claims of performance failure (see Appendix D).

In the commercial sector the importance of the continuity of system operation usually relates to the effect that a loss of that service will have on the building or business.  In a major commercial office environment this may be whether the building can continue to be occupied in the event of the loss of the ventilation plant, and for how long this occupancy can continue.  This is to a large degree tied in with the statutory regulations as they apply to the ventilation of the building.  It might also depend on whether equipment or processes in the building can continue to operate.  The level of maintenance applied, and the resources made available to facilitate it should reflect the magnitude of risk represented by a system failure.

The extent of the maintenance required for a building will relate to the technical complexity of the building services, the robustness of the plant installed and the availability of maintenance staff to carry out the necessary repair in the event of a failure.

Maintenance may be required to achieve system performance standards (comfort conditions, energy costs, sustainability goals etc.) and to meet operational goals, e.g. maintenance may be required to retain a certified building performance or star rating level.

Maintenance roles and responsibilities

Maintenance lifecycle

Maintenance should be considered throughout all lifecycle phases of the HVAC&R system including the design, construction, commissioning and operation phases.

Figure 2.3 Maintenance considerations during system lifecycle

Effective maintenance management is only possible when all stakeholder roles and responsibilities are understood by all parties. The following discussion on roles and responsibilities highlight some of the issues that need to be addressed by the various stakeholders in a building and its services.

Building owner

The building owner, system owner or client (the demand organisation) plays a significant role in the maintenance process. They first set the objectives for maintenance and it is these objectives that determine the structure and format of the maintenance program.

Owners’ objectives for system maintenance can include:

• Meeting legal obligations,
• Asset protection and enhancement,
• Optimising economic outcomes,
• Risk management and minimisation,
• Marketing or leasing commitments,
• Indoor environment quality,
• Energy and water ratings or other performance goals
• Corporate image or reputation.

The maintenance objectives selected by the owner should then be included in the design brief to be given to the system designers and for buildings that are already operational to the maintenance team.

The level of importance and resources that an owner directs towards maintenance will have a direct effect on the success and effectiveness of the maintenance program.

Maintenance programs need to be adequately resourced and include the necessary education and training to service personnel, building tenants and building occupants. Maintenance programs need to be supported and lead from the highest level in an organisation and roles and responsibilities, with regard to maintenance and maintenance management, need to be well defined.

Successful HVAC&R performance maintenance is rarely reliant on one party, in a typical application it is critical that a team is developed that includes the owner, HVAC&R maintenance contractor, controls contractor (if separate) and plumbing and electrical contractors when required.  Sometimes tenants will need to join the team to ensure full compliance with the maintenance plan.  The owner (or their representative) should be the catalyst for this team coming together at an appropriate frequency to ensure success and continuous improvement.

Building owners can be responsible for tenant HVAC&R equipment for which there is a legal requirement. Tenants and occupiers need to be informed of the imperatives for system maintenance and should be encouraged to facilitate all reasonable requests for access to HVAC&R plant for maintenance.

When an owner is delivered a new HVAC&R system they are responsible to ensure the system (or modifications to a system) been commissioned to demonstrate that it is capable of achieving the design performance but also that detailed asset registers and Operations and Maintenance Manuals have been provided.

In relation to health and safety the owner has significant obligations to ensure that there is a system of health and safety on the property and that all staff are inducted and use the system.  Just as with ensuring system performance a team approach is required to ensure safety with owners and contractors each needing to ensure that safe systems of work are documented and applied.

System designers

It is the responsibility of the designer to produce HVAC&R system designs that will satisfy the owners’ brief and comply with any stated maintenance policy. Building solutions proposed by designers need to address the following maintenance issues within the normal project constraints:

• Life cycle costs of the system,
• Reliability of the system and components,
• Maintainability of the system and future maintenance strategy,
• Location of and safe access to the services,
• Reliable and appropriate control systems,
• Monitoring, metering and recording facilities,
• Certification of commissioning data and results,
• Operating and maintenance information for system,
• Detailed maintenance schedules and instructions,
• Recommendations on maintenance management.

Designers are best positioned to develop the design/maintenance philosophy for a building or system which can be laid out in Operations and Maintenance Manuals.

Safety-in-design

Designers have a legal responsibility to ensure that their design will be safe to operate and maintain. This design responsibility continues through the construction process, either by the original designers or by subsequent designers if further design or modification to the original design is undertaken.

Designers have a responsibility to inform their clients of the ongoing maintenance or life cycle costs of their design proposals and of the future responsibilities of system owners and operators with regard to maintenance.

Work Health and Safety imposes an explicit legislated duty on the system designer to determine the maintenance regime for the system plant and to design for adequate access to that plant to allow the required maintenance to be performed. The fundamental requirement is to ensure that plant with a required performance maintains that performance safely.

HVAC&R system installation contractors

Regular inspections should be made during system installation by HVAC&R system contractors or their representatives to ensure:

• Adequate and safe access to plant is provided,
• Original specification for materials and equipment is complied with,
• Equipment installation requirements are complied with,
• As-installed drawings supplied are accurate,
• Operating and maintenance manuals are complete,
• Commissioning procedures are carried out appropriately,
• The installed system meets the design intent.

Contractors have a responsibility to inform owners of the ongoing maintenance requirements for the plant and of the future responsibilities of system owners and operators with regard to that maintenance.

Specific requirements for operating and maintenance manuals, and the transfer of design related HVAC&R information, is required if systems are expected to operate to the design standard throughout their life.  The owner should not accept any HVAC&R system without the installation contractor providing suitable Operation and Maintenance Manuals (see Appendix C).

Commissioning personnel

Correct commissioning of a system is essential for optimum system performance and the implementation of a successful maintenance program. Because the commissioning data will form the basis of the maintenance plan, the personnel commissioning the system also have maintenance responsibilities. Commissioning personnel should ensure that:

• Commissioning procedures for plant and systems are carried out appropriately,
• Commissioning data is properly recorded and logged,
• System commissioning data complies with system design data,
• Any non-compliance is reported and addressed.

Specific requirements for commissioning, commissioning management and commissioning documentation are required to be met if the building construction is under a Green Star accreditation regime.

Periodic re-commissioning of a system or parts of a system is also required for optimum long-term system performance (refer to Clause 7.2) and may be included in the maintenance plan.

Building/Facility managers

The building manager, facility manager or maintenance manager has a significant maintenance responsibility. A primary role of the manager, who usually act on behalf of the owner or demand organisation, is to ensure that the building and its systems are functioning optimally

Managers drivie the maintenance process and also:

• provide the link between system maintainers and building tenants and occupants,
• need to respond to complaints quickly and efficiently,
• ensure the building occupants are satisfied,
• often provide a supervisory role for maintenance staff and contractors,
• maintain documentation such as the asset register and operating and maintenance manuals,
• monitor, meter, record and report system performance, ensuring that performance data is available to relevant maintenance team participants
• communicate maintenance issues,
• resolve access issues,
• report on the maintenance effectiveness,
• arrange for the periodic review of maintenance plans and procedures.

Successful maintenance management relies on the on-going commitment of managers to maintenance planning, maintenance funding and user education.

Maintenance contractor

The maintenance contractor needs to supply system maintenance in accordance with the maintenance contract.

The maintenance contractor must ensure that maintenance personnel are appropriately trained, skilled and licensed to carry out the work and are supervised as appropriate.

The maintenance contractor should keep abreast of developments in all areas and advise the owner when it is considered that modification can be made to the plant to economic advantage.

Contractors may also have a responsibility for the formal reporting of ongoing sustainability or performance indicators associated with particular systems.

Modern maintenance is a partnership of stakeholders and the maintenance contractor needs to ensure that the knowledge loop, regarding HVAC&R services, between system maintainers and operators is facilitated.

The maintenance contractors’ role can include:

• Inspection, testing and monitoring,
• Repair and replacement,
• Compliance activities and records,
• Purchase and installation of plant,
• Purchase and installation of spares and consumables,
• Control of onsite stores and spares,
• Energy management and reporting,
• Water management and reporting,
• Supervision and assessments,
• Cost control,
• Complaint response and trouble shooting.
• Analysis of performance data
• Developing strategies for continuous improvement
• Developing a system of work that ensures the health and safety of all personnel
• Maintaining asset registers and Operation and Maintenance Manuals

Maintenance service personnel

It is essential that maintenance service personnel be appropriately trained, skilled and supervised for the work undertaken. They need a good understanding of how each system should operate and in particular fully understand the control system being applied to the system.

Maintenance personnel require a range of certifications and licenses to carry out the required maintenance work on HVAC&R systems often in relation to refrigerant handling, boiler work, water treatment, hydraulic services and electrical work.

Service personnel are responsible for their own safety and to use the documented work methods as well as participate in the continuous improvement of these systems.

Other trades

Effectively maintaining HVAC&R systems will often require the collaboration of a team of specialists including, BMCS/controls contractors, electrical contractors, and hydraulics contractors.

It is the responsibility of the owner to ensure that this team is well informed and are aligned in their understanding of goals that are to be achieved.

Tenants

Tenants need to be instructed in the correct operation of the system and this should be in lay terms. Tenants need to be engaged by the building manager on the energy efficiency/sustainability features of the building systems.

Tenant fit-outs can impact on system performance and HVAC&R systems may need some redesign as a result of fit-out activities. Rules or procedures need to be in place to ensure that any negative impacts of tenant fit-outs on the overall building and system performance is mitigated.

Tenant systems can be connected to or be separate from base building systems. They can be complex and require considerable maintenance in themselves.

Tennant systems are also covered by the NCC and building and health law. Building and health laws do not typically recognise any tenant/owner contractual arrangement but generally makes the building owner responsible for compliance. Tenants and occupiers need to be informed of the imperatives for maintenance and should be encouraged to facilitate all reasonable requests for access to HVAC&R plant for maintenance.

Occupants

Occupants need to be aware of the correct operation of the system and the influence that their behaviour can have on system performance.

Well informed occupants can alert maintenance managers to potential problems and also help to identify opportunities for future or further system improvements.

Occupants form part of the communications and knowledge loop between system operation and maintenance.

Figure 2.4 HVAC&R system knowledge loops

Maintenance health and safety

Much of the maintenance discussed in this application manual is associated with the testing of installed equipment to ensure that the plant will operate safely and when required.  When plant does not operate correctly the required operating conditions may not be achieved and risks to health and safety of occupants may increase.

Many of the items associated with safety are covered by statutory requirements, for instance the testing of pressure relief devices or the inspection of fire and smoke dampers. Building owners and managers should ensure that they are fully aware of all of their legislated health and safety duties.

However, this manual is also concerned with the way in which the maintenance work is carried out, both for the safety of the operative performing the maintenance and also for that of the occupants of the building or facility. It is important to ensure that the methods of work are safe for the operatives and this might include, for example, safe access and working conditions for the cleaning of a cooling water system.

The requirement to provide a safe work place, whether it is for in house maintenance staff or for the staff of external providers, is legislated throughout Australia on a state by state or territory basis. All jurisdictions base their WHS/OH&S legislation around the “duty of care” concept and effectively put the responsibility for determining what is safe onto the building owner or occupier the PCBU, and the employer of the personnel undertaking the work.

System owners and operators and maintenance staff employers should ensure that they are fully aware of their legal responsibilities with regard to occupational health and safety requirements within the WHS/OH&S jurisdiction that the system is located.

Compliance with mandatory maintenance

Owner/Operator responsibility

Compliance with the law, either commonwealth or state based, and the associated statutory regulations applying to the maintenance of a particular building or system is the minimum maintenance requirement that must be satisfied. Failure to meet these minimum requirements could result in severe legal penalties for building owners and operators, particularly where the health and safety of occupants is impacted.

Certification that the required maintenance has been carried out on the plant may be necessary to provide assurance that the mandatory maintenance obligations are being met.

Legal requirements regarding the maintenance of HVAC&R systems can vary from state to state (and territory) in Australia. System owners and operators should ensure that they are fully aware of their legal responsibilities with regard to system maintenance in the jurisdiction that the system is located.

These specifically cover:

• Safety measures, emergency warning, emergency lighting, smoke control etc.
• Mechanical ventilation and hot water, warm water and cooling water systems
• Energy efficiency installations.

Maintenance and NCC building measures

From a building regulation perspective, the term ‘maintenance’ is used to describe those activities required to ensure the ongoing performance of building measures, the building components, systems, measures or strategies (which includes safety measures), or equipment and energy efficiency installations, required to meet the Performance Requirements of the NCC Volume One.

The general expectation is that systems and buildings are capable of performing to the Standard to which they were installed and constructed. Australian jurisdictions differ in the way these expectations are regulated.

Maintenance of safety measures

The requirements for safety measures maintenance must comply with any specific state or territory requirements in force in the jurisdiction of the building. Safety measure means any measure (including an item of equipment, form of construction or safety strategy) required to ensure the safety of persons using the building. Maintenance of safety measures in a building is often called essential services maintenance or ESM.

In many jurisdictions, maintenance provisions form an integral part of the preliminary design and building approval process, while in others maintenance is covered through additional regulations and legislation outside of the building approval process. Care should be taken to ensure that relevant State or Territory legislation is satisfied, as maintenance requirements differ between jurisdictions, particularly in the finer detail.

Unless the standards of maintenance performance are specified through the relevant legislation the following list may be used to determine the standard of performance that HVAC&R systems and equipment should continue to achieve, by referencing the corresponding NCC V1 provisions and associated referenced standard.

Building Fire Integrity C3 (AS 1851):

• Fire dampers, smoke dampers, - C3.15
• Fire protection at service penetrations through elements with a required FRL - C3.12, C3.13, C3.15
• Fire-protected air ducts - C3.15

Smoke hazard management systems in accordance with E2.2 (AS 1668.1, AS 1851):

• Air pressurisation systems for fire-isolated exits – E2.2
• Mechanical smoke exhaust systems and automatic smoke-and-heat vents – E2.2
• Air-handling systems that do not form part of smoke hazard management system and which may unduly contribute to the spread of smoke – E2.2
• Miscellaneous air-handling systems serving more than one fire compartment and other air-handling systems serving carparks and kitchens – E2.2
• Atrium smoke control systems - Specification G3.8

For HVAC&R systems, safety measures maintenance is generally limited to the fire and smoke control features of ventilation or air conditioning systems.  The legislative and regulatory framework in each state and territory refers to these features by a different name, variations of essential fire safety installations, provisions or measures are used. In all cases records are required to verify maintenance provision against statutory requirements where these are in place. Complete and accurate records are required to enable annual certification and sign off against the requirements.

In many jurisdictions maintenance provisions form an integral part of the preliminary design and building approval process. In this case building approval documentation will contain explicit information on the plant that is required to be maintained and the standard of maintenance required. Other jurisdictions may refer to Australian Standard AS 1851 requirements for essential services maintenance.

The objective of AS 1851 is to maximize the reliability of the fire and smoke control features of air handling systems. The standard is intended to provide a systematic and uniform basis for building owners and managers, regulators, contractors, insurers and others to implement and administer inspection, test, preventative maintenance and survey programs applicable to these systems. AS 1851 section 13 contains a series of maintenance schedules for plant associated with the fire and smoke control features of HVAC systems. The maintenance schedules in this application manual have been aligned with AS 1851 requirements where appropriate.

AS 1851 provides a four-stage approach. Stage 1, outlined in section 13 of the standard, covers standardized requirements for the inspection, test, preventative maintenance and survey of fire and smoke control features of HVAC systems in buildings. Stage 2 covers records, stage 3 reporting and rectification and stage 4 is the annual condition report. The standard includes Table 13.2.1 which outlines the application of AS 1851 to HVAC systems.

APPLICATION OF AS 1851 TO HVAC&R SYSTEMS

NOTE: Smoke exhaust systems, smoke control systems and exit pressurization systems are required to be tested at least annually to demonstrate they are capable of performing to the Standard to which they were installed. In the case of the following systems, this requires measurement of parameters required by AS/NZS 1668.1 or the relevant building codes including:

(a) Pressurization systems — Doorway velocities, door opening forces, restoration times, etc.

(b) Smoke control systems — Differential pressures, etc.

(c) Smoke exhaust systems — Airflow rates.

Figure 2.5 Table 13.2.1 Reproduced from AS 1851-2012

AS 1851 also includes requirements for the maintenance of the other fire and smoke related elements of a building’s HVAC system including;

• fire and smoke dampers,
• air control dampers and motorised relief dampers,
• outdoor air intakes
• kitchen exhaust systems, and
• motor control centres.

Maintenance of other building measures

Apart from safety measures the ongoing performance of all the building’s components, systems, measures, strategies or energy efficiency related equipment and installations, that are required to meet the Performance Requirements of the NCC Volume One, also need to be ensured. This includes:

Mechanical ventilation and air conditioning systems (AS 1668.2, AS/NZS 3666.1)

• Supply and exhaust mechanical ventilation system and components – F4.5, Part J5
• Air conditioning systems and components – F4.5, Part J5
• Kitchen local exhaust ventilation - F4.11
• Carpark mechanical ventilation systems - F4.12

Refrigerated chambers, strong rooms and vaults - G1.2

The NCC Volume One also contains requirements for the performance of equipment and plant associated with the energy efficiency provisions.

Maintenance and energy efficiency

The NCC contains requirements for the energy efficiency of building services. The particular energy efficiency requirements for HVAC&R systems and components are given in Part J5.  In addition to the installation requirements, NCC provisions address the control of air conditioning systems, the operation of fans and pumps and the ongoing performance of required supply and exhaust ventilation systems.

The energy efficiency provisions for services contained in Part J5 must be maintained to ensure that systems continue to operate at their design performance over their full operational life. A lack of maintenance would create performance inefficiencies and result in increased energy usage.

Apart from the air, water and refrigeration systems associated with air conditioning and ventilation, energy efficiency installations that need to be maintained include the ancillary plant, equipment and components required by the NCC Volume One Section J such as:

• Adjustable or motorised shading devices
• Time switches and motion detectors
• Room temperature thermostats
• Plant thermostats
• Motorised air dampers and control valves
• Reflectors, lenses and diffusers of light fittings
• Heat transfer equipment
• Plant using energy from an on-site renewable source or reclaimed process energy.

Maintenance and microbial control

The requirements for the maintenance of mechanical ventilation, hot water, warm water and cooling water systems must comply with the state or territory requirements in force within the jurisdiction of the building or facility location.

There are specific compliance regimes for cooling towers and heated water systems in all states and territories. These are covered by public health based legislation in most states and territories, except Queensland where they are covered by WHS legislation. Most of these regulations are based on AS/NZS 3666.2 and/or AS/NZS 3666.3 compliance and verification, however they all have specific additional administrative and technical requirements that must also be complied with.

AS/NZS 3666.2 specifies the minimum requirements for the operation and maintenance of air-handling and water systems of buildings. The objective of these maintenance requirements is to assist with the control of microorganisms in building systems particularly those associated with Legionnaires’ disease, Pontiac fever, Humidifier fever and Hypersensitivity Pneumonitis. AS/NZS 3666.3 specifies the performance-based alternative to managing microbial control in cooling water systems, based on a risk assessment and management approach supported by a strict monitoring and control regime.

Maintenance, refrigerant handling and refrigeration safety

Refrigerants are classified in accordance with AS/NZS ISO 817. This standard classifies refrigerants into safety groups according to their toxicity or flammability. The standard also lists the ozone depleting potential (ODP) and global warming potential (GWP) of the refrigerants.

Given the potential safety and environmental impacts of many refrigerants, leaks of these chemicals from HVAC&R systems are not allowed. The practice of topping up a refrigeration system with SGG refrigerant is prohibited as this indicates the presence of a refrigerant leak which must be located and repaired immediately.

Maintenance of systems containing fluorocarbon refrigerants (HCFC or HFC) is covered by the Australia and New Zealand Refrigerant Handling Code of Practice (2007). This maintenance can only be carried out by personnel licensed under the Ozone Protection and Synthetic Greenhouse Gas Management Act 1989 and the Ozone Protection and Synthetic Greenhouse Gas Management Regulations 1995. The Australian Refrigeration Council (ARC) is the body responsible for issuing these licenses. It is illegal to handle these gases without the correct ARC license.

Maintenance and handling requirements for other refrigerants including ammonia, hydrocarbons and CO₂ are generally based on industry standards AS/NZS 5149 parts 1 to 4, particularly part 4 on operation and maintenance. Ammonia is also covered by the Victorian Code of Practice on Ammonia Refrigeration.

Maintenance and building rating schemes and tools

Building (design and performance) rating schemes are non-regulatory systems that are increasingly being adopted as the measure of a buildings’ sustainability and environmental performance. They were once considered voluntary but are increasingly being required through development contracts and leases.

The main rating schemes used in the Australian commercial building sector are:

• Green Star, WELL ratings
• National Australian Built Environment Rating System (NABERS)

All of these schemes require that HVAC&R systems continue to operate as effectively as, or better than, their initial rating. This is only possible with effective system maintenance and ongoing system tuning.

Maintenance and HVAC system rating tools

The HVAC rating system Calculating Cool contains particular requirements for maintenance and maintenance management.  Where HVAC systems have been assessed by the tool and a star rating assigned the maintenance provisions have to be retained for the life of the assessment.

Maintenance to protect the environment

Examples of environmental considerations, often described as sustainability objectives, associated with HVAC&R systems include:

• System life cycle assessment.
• System water use.
• System energy use, (renewable and non-renewable sources).
• Refrigerant application and handling.
• Monitoring, metering, recording and reporting facilities.
• Indoor environmental quality.
• Contamination control procedures.
• Management of consumables (renewable versus disposable, cleaning water use).
• Waste management.
• Disposal of contaminated materials.

System sustainability objectives should be included in the building owners specification.  Maintenance activities and outcomes that relate to system sustainability should be reported by the maintenance contractor to the owner or manager.

System performance and benchmarking are significant issues when considering the sustainability of HVAC&R systems. What can’t be measured can’t be managed so monitoring, metering, recording and reporting practices are all essential to meaningful sustainability claims.

The assessment of maintenance contractors performance should include an evaluation of their sustainability practices. The environmental footprint of maintenance service providers, their energy and water use, their transport arrangements, their paper use, their reclamation and recycling policy and the like should all be considered.

Life cycle costing

The common denominator in all approaches to maintenance is the impact on the business of costs associated with the plant.

Life cycle costing for a facility or system is a defined method for assessing all the significant costs of system ownership and operation over a specified time period and expressed in equivalent monetary terms.

Life cycle costing is an important tool for system designers, owners and financial planners.

Knowledge of the lifecycle costs associated with systems and equipment can aid:

• Design considerations for system and equipment selection
• Operating decisions, whether to repair or replace plant
• Management assessments of system or equipment effectiveness

Further information on life cycle cost methodology, that may be useful to owners, financial planners and system designers, is contained in Appendix E.

Plant service life

Service life can be defined as the time during which a particular system or component remains in its original service application. Replacement may occur for a variety of reasons including:

• Premature failure.
• Reduced reliability.
• Excessive maintenance cost.
• Unavailability of spare parts.
• General obsolescence.
• Changed application requirements (changes to space occupancy or building load).
• Environmental considerations (refrigerant phase down).
• Energy price increases (more efficient plant available).
• Changes to building function.

Table 2.1 provides a listing of likely service (economic) lives for HVAC&R equipment. A range of years is given for each item in the Table. These are based on a ‘standard’ operating regime of up to 10 hours a day, 5 days a week, with the plant working at as-designed operational duty, in an environment suitable for its design and manufacture and maintenance generally to manufacturers recommendations.

There are a range of factors that can impact on the actual service life. The following service life factors can reduce the potential economic life of the plant:

• Maintenance – Inadequate level or lack of maintenance applied.
• Poor Access – Insufficient access for maintenance to be carried out.
• Design and specification – Departure from the original design assumptions.
• Operation – Actual operating hours or conditions higher or lower than designed.
• Misuse – Where plant has been operated incorrectly.
• Installation – Standard of installation and commissioning applied.
• Period of use – Where plant has been unused for a significant period of time.
• External environment – weather, pollution, coastal etc.
• Internal environment – Temperature, humidity, moisture, corrosive etc.

Additionally, the advent of improved alternative technology can compromise the effective economic life of existing plant.

Maintenance and noise issues

Plant and system noise is another issue regularly impacted by maintenance.

Information on noise measurement is given in AS 1055. Recommended design sound levels and reverberation times are given in AS 2107.

Guidance on noise control on maintenance sites is given in AS 2436. Information on the noise labelling of plant and equipment is provided in AS 3781.

Table 2.1 Economic (service) life of equipment

Note:  The above values are given for guidance only. The assumed life of a plant item may vary depending on the particular project under construction.

MAINTENANCE IN DESIGN, INSTALLATION AND COMMISSIONING

General

To allow the maintenance of plant to be carried out quickly and efficiently it is essential that all of the plant is safely accessible, all items are identified, and all services required are available.  This should have been resolved during the design and construction period.

Maintenance issues need to be considered throughout the lifecycle of a HVAC&R system. As a guide the following list of maintenance considerations should be accommodated during the design, construction and handover stages of a project.

Design considerations

All HVAC&R systems should be designed to be as simple, reliable and sustainable as possible while being fit for purpose and providing the required function. This is particularly true of control systems associated with HVAC&R systems.

System designers are best placed to develop the design/maintenance philosophy for a building or system. The maintenance philosophy should be developed based on the maintenance objectives of the owner and the final design should take full account of the maintenance policy, refer section 4.

The maintainability of plant and systems is an important determinant in how energy and water efficient the systems will be over their whole life cycle. Something that is difficult to maintain and tune will be much less likely to operate efficiently and as intended than something that is easier to maintain. Designers should carefully consider the complexity of the systems they conceive with respect to maintenance and operating requirements and the maintenance provider’s ability to deliver these services.

Maintainability also relates to issues of equipment selection and ongoing maintenance cost and convenience. Consideration should be given to the standardization of common components in a new installation, same make/type of pumps, valves, and the like to reduce the number and type of spare parts that are required to be held or accessed. The ability to readily and cost effectively access spare parts also needs to be considered during equipment selection to help ensure that the life cycle costs of the systems are minimized.

Similarly, consideration should be given to the use of specialist or non-specialist plant and local or exotic plant origins. The availability of local maintenance knowledge, equipment (spares), training and support can improve both system maintainability and sustainability. The use of an established technology rather than a new technology in a design may be more appropriate in some cases due to the unavailability of future maintenance skills and resources.

Designers can reduce or minimise future maintenance by using high quality components (reduced mean time between failure), by using components or systems requiring no maintenance (passive systems) or by using duplicate services (run/standby pumps).

Designers should consider the commissionability of the system. Commissionability relates to the extent to which the design and installation of HVAC&R systems facilitates system balancing and tuning to required performance.

Designers should consider “building in” systems for monitoring and feedback of plant operation into their designs. Built in monitors can be linked to building management systems and can be associated with future condition monitoring maintenance strategies.

The ability of system designers to make cost effective changes to the design with regard to system maintainability, commissionability or sustainability is most significant in the early stages of design. As the project progresses through detailed design, installation, handover and operation the costs of any required changes to the system rise dramatically, refer Figure 3.1.

Figure 3.1 Relative cost of changes during a construction project

Design checklist

Apart from designing HVAC&R systems for sustainable operation by minimising energy and water use allowances in the design must also be made to support the ongoing sustainable operation of plant. This includes easy access to the meters and monitoring points provided on the system.

The following sustainability checklist is provided for HVAC&R system designers and installers.

Lifecycle costs

Energy use

Water use

Noise

Refrigerant application

Maintainability and access

Commissionability

Reliability

Monitoring and metering

System optimisation and tuning (ability)

Indoor environment quality

External environmental impacts

Materials and embodied energies

Consumables and future access for replacement

Safety provisions

Risks associated with maintenance access include:

• Working at heights – On roofs, highwall, ceiling mounted plant
• Working in confined spaces – Plantrooms, motor rooms, basements, risers, shafts
• Working with electricity – Lock out/Tag out must be facilitated and observed at all times
• Working with hazardous chemicals, refrigerants, oils, water treatment chemicals, air and water filters
• Working with hazardous work procedures – hot work grinding, welding, brazing

Maintenance related safety provisions that should be made during installation include the following.

• Ensure the provision of all necessary safety rails.
• Ensure the provision of all safety guards and equipment enclosures.
• Provide all safety signs in accordance with AS 1319.
• Label all items of plant or systems to allow ready description in case of failure or to allow the service person to identify items requiring attention.
• Pipes, conduits and ducts should be labelled in accordance with AS 1345.
• Provide switchboard cards to identify circuits and controls without recourse to drawings or diagrams.
• Provide any necessary warning signs for the safe operation and working of the plant or equipment.

Beams or lifting devices should be provided to allow the safe handling of heavy items of equipment.

Plant room or plenum lighting must be sufficient for the safety and productivity of the service person.

Access for maintenance

Good access is essential to allow plant to be maintained easily and safely.  Access for maintenance has always been a requirement of AS/NZS 3666.1.  In addition, the provision of safe access for maintenance for HVAC&R plant is a legal requirement of WHS/OH&S legislation. Service providers working in unsafe situations put building owners and occupiers at risk of prosecution and litigation in case of accident or injury.  Maintenance service providers have a legal obligation to provide safe working conditions for their personnel.

Because of the range of equipment in the marketplace, and the different sizes and shapes of equipment serving the same purpose, it is difficult to quantify, in generic terms, the amount of access that would be needed by HVAC&R plant.  For example, a shell and tube heat exchanger will have different spatial requirements for access than a plate heat exchanger.  Manufacturers can provide the necessary guidance.

Safe access

Access for maintenance includes the provision of access for a range of purposes including maintenance, inspection, measurement, operation, lubrication, adjustment, repair, replacement and other maintenance related tasks.

The requirement for safe access is a legal requirement and the first responsibility for ensuring safe access rests with the initial designer.

Every piece of HVAC&R plant requiring maintenance or service is a workplace for the service technician. Australian WHS/OH&S legislation requires the entire supply chain to consider the safety of the maintenance personnel, and to minimise any identified risks.

Access provisions should include:

• Provide access to plant rooms and to any other equipment rooms
• Provide fixed platforms, walkways, stairways and ladders where required to AS 1657.
• Provide sufficient space around plant for the removal of parts and the safe productive performance of service.
• Provide sufficient access for the replacement/upgrade of plant.
• Provide inspection covers to allow observation of specific items of plant.
• Access panels or doors should be large enough and located to allow ease of entry for service person to inspect and clean and for removal or replacement of parts.
• Access doors should open against the air pressure.

Access standards

There are a range of Australian Standards that relate to access including AS 1470, AS/NZS 1892.1, AS/NZS 2865 and AS/NZS 3666.1. Many of these standards form mandatory requirements of various regulations.

AS/NZS 1892.5 - Portable ladders - Selection, safe use and care

AS 2865 - Confined spaces

Barriers to safe access

The provision of better, safer access typically increases capital costs, so cost can become a barrier to safe access. This is particularly evident when the person paying for the access (for example a builder or developer) is not the person who will incur the additional ongoing costs related to poor or inadequate access.  A benefit cost analysis might easily justify the additional cost in for example steel walkways to remove 25 years of monthly service access via ladder, but if the benefits are not available to the decision maker then the output of the analysis might favour the more expensive ladder approach.

Because the responsibility for safe access can be invested in several stakeholders in the supply chain, this division of responsibility may lead to recommendations but inaction and ultimately sub-optimal outcomes.

Platforms, walkways, stairways and ladders

AS 1657 covers the design, construction and installation of fixed platforms, walkways, stairways and ladders, including minimum dimensions and slip resistance: The minimums applied for safety may not be adequate for effective maintenance.

• Headroom: 2100 mm (Recommended) -  2000 mm (AS 1657 Minimum).
• Width of stairs: 750 mm (Recommended) -  600 mm (AS 1657 Minimum).

The provision of access must be appropriate to the frequency at which certain tasks will be carried out.

Figure 3.2 Suggested decision tree for determining safe access provisions.

Access around plant

All plant, valves, controls, terminal units, etc which require frequent maintenance and operation should have permanent, clear and immediate access with adequate space provision to carry out the maintenance tasks.  Equipment should be laid out in a way that creates shared access space between items which are not maintained simultaneously.

Design drawings should show access for maintenance provisions and space for withdrawal of plant items e.g. motors, filters, fan shafts.

Ductwork access

Rigid duct construction standard AS 4254.2 requires that all ductwork is installed allowing for the access required to carry out testing, commissioning and maintenance routines.

Access to ductwork systems for maintenance purposes is a requirement of a range of Australian Standards including AS 1668.1(access for kitchen exhaust duct cleaning, access to fire and smoke dampers), and AS/NZS 3666.2 (access for commissioning and maintenance including access to areas where moisture can occur and access to filters).

Solving access problems

Retrofitting safe access solutions to solve existing access problems is sometimes technically difficult or impractical to achieve. A risk assessment informs what is reasonably practicable.

One solution is to reduce the frequency of access required for maintenance, by making appropriate equipment selection (some plant and equipment types require less maintenance than others) or by the installation of remote monitoring equipment (to replace or reduce the need for inspection, see Section 6).

Controls

The fundamental purpose of controls is to regulate the performance of plant to meet system operational requirements. Control systems act to achieve and then maintain a set condition. Controls play a key role in energy efficient operation and sustainability. Control irregularities can be a significant cause of inefficient operation and excessive energy consumption in HVAC&R systems.

Control systems can fail or perform poorly for the following reasons:

• Poor design
• Poor location or installation of sensors
• Low quality sensors
• Oversized dampers and valves
• Incorrect commissioning
• Inadequate maintenance or system tuning.

The most important aspect of control systems is that the operator and maintainer of the system understand the control logic and design intent. Controls need to be well managed and maintained and if the logic and intent of control systems cannot be readily understood the system will need to be simplified or training provided.

Control systems can be relatively simple or highly complex. As the capability of the control system rises the costs and complexity also tend to rise leading to an increasing level of operating knowledge and maintenance expertise required, see Figure 3.4.

Figure 3.4 Control system capabilities

The effective functioning of any control system will depend on the correct location, positioning and calibration of each control sensor.

Recalibration of controls and sensors is a critical factor in the ongoing maintenance and system tuning regime. Constant recalibration of sensors can be time consuming and selection of high quality control components at design stage can significantly reduce recalibration requirements and set point drift.

Where occupants are provided with individual or general control interfaces, training or documentation should be provided to ensure that they appreciate the mode of operation that will produce the optimum results.

For centralized control systems access should be restricted to authorised personnel only.

Intelligent controls can be arranged for self-monitoring which can assist in maintenance management and delivery.

Monitoring and metering

What can’t be measured can’t be managed and the monitoring and metering facilities provided on a system are essential to its effective future management.

Ensure the provision of ample gauges, meters, and other instruments, of correct range and accuracy, to allow the proper testing and performance monitoring of all items of equipment. Meters should be applied to incoming utilities like water, electricity, gas, oil and LPG.

Ensure that meters and sub meters are appropriately zoned to reflect separate tenancies and sub-tenancies. Ensure that all services are monitored including energy, water, temperature, flow rate, pressure as appropriate. Metering and data analysis is enhanced if major plant such as boilers, chillers, cooling towers, air handlers and motor control centres are separately metered. Meters should also be incorporated into final electrical distribution boards. Any other large point loads should also be separately metered and monitored.

Monitoring provides system performance data which can be compared against benchmark data. Monitoring on a more detailed level can provide valuable information on patterns of consumption and plant loading.

Systems with legislated safety or sustainability requirements attached may require monitoring and recording to provide evidence of ongoing compliance with regulations.

Meters and other measuring devices need to be regularly calibrated to ensure that the measured performance data is accurate and correct.

Owners and operators should be given sufficient instruction to show how meters can be used to compare consumption and monitor operating performance.

Refrigerant management

It is important that refrigerant working fluids are retained within their systems.  Designers should consider the incorporation of refrigerant leak detection and automatic pump down facilities into their system designs, beyond the minimum requirements of AS/NZS 5149.2.

From a performance, environmental, safety and cost perspective any refrigerant leak must be identified immediately and repaired as soon as practicable.

Automatic pump down facilities can help minimise the loss of refrigerant in the event of a system leak. Pump down facilities are also useful for maintenance activities where refrigerant systems need to be drained for maintenance work. Some refrigeration equipment incorporate pump down in their design and manufacturers should be consulted.

Documentation

Asset register

The asset register (or plant register) is a fundamental component of the maintenance management plan.

An asset register is a record of all assets associated with the HVAC&R systems, components of a system are divided into sub-assets. HVAC&R plant will itself be a sub-asset of a whole building asset list.

Each asset and sub-asset is given a unique identifier on the register which then provides a structure for recording and retrieving maintenance information. These asset identifiers should be included on the “as-installed drawings” provided with the O&M manual.

As a guide, the following is a list of information which should be recorded when identifying items in the asset register:

• Asset number/identifier of each item of equipment.
• Function of the equipment or system.
• Any maintenance required by regulation.
• Description of the control system and a schedule of all set-points.
• Location in the building.
• Manufacturer’s / suppliers / installer’s name and contact address.
• Equipment/ system description (model name)
• Equipment/ system designation (model number)
• Any unique identification (serial number)
• Rating or capacity of equipment or system.
• Associated spare parts inventory.
• Date of installation / manufacture / replacement.

Each item listed should be included in the maintenance program.

Asset lists should be provided in an electronic format to facilitate the construction of maintenance schedules and building log books, and to support the operation of maintenance management systems and field data capture and reporting devices.

Plant can be electronically tagged with the asset register information and identified using bar codes, smart tags or similar.

Operating and maintenance manuals

Every HVAC&R system should be provided with comprehensive system information in the form of operating and maintenance manuals, these are a requirement of AS/NZS 3666.1 for buildings. Operating and maintenance manuals are detailed technical manuals containing:

• System designer’s contact details.
• System installer’s contact details.
• Installation team.
• Scope and system description.
• Design intent and functional descriptions for all systems.
• Design and performance criteria.
• Control strategy descriptions.
• Controls, power and wiring diagrams.
• Operating protocols for the system
• Architectural and as-installed building services drawings
• System details; function, location, area served, capacity
• Physical details of the plant, equipment and systems
• Commissioning records; procedures and results
• Manufacturers’ literature
• Detailed equipment and system maintenance information.
• Location of test, access and inspection points

Operations described in the manual should include at least the following activities:

• Stop/start procedures.
• Fault finding and emergency procedures.
• Routine safety checking.
• Routine maintenance and troubleshooting procedures.
• Routine testing and adjustment of controls.
• Routine replacement of consumables.
• Routine lubrication.
• System tuning procedures.
• Record keeping requirements (log books, meter readings, liquid levels).
• Associated housekeeping and safety protocols.
• Others that may be appropriate to the asset.

Comprehensive information on the benefits, content and format of operating and maintenance manuals is provided in Appendix C.

User handbooks

A user handbook provides the operating instructions in a lay or non-technical language and format and are designed to inform building occupants on how they can make best use of systems in a building.

In particular the user handbooks should emphasise the performance features of a design.

This includes the provision of sufficient information to:

• The system features and system design concepts.
• Normal system operation and occupant-based controls.
• Afterhours system operation.
• Emergency system operation.
• Emergency procedures.
• Fault reporting.

When compiling a building user guide, it is important to cover the following three essential areas for each system and all user-interactive control devices:

• What is it?
• How does it work?
• How can building users work with it?

In addition to building user guides, informative signage can be installed at appropriate locations around the building to include and reinforce the same information. It is essential that system owners, users and maintainers be educated in the correct operation of the plant so that the benefits from system sustainability can flow.

Water and drainage

Many maintenance operations require the washing and cleaning of components. Others require that equipment and systems be drained down during certain procedures. Designers and installers need to:

• Provide water and drains adjacent to filter cleaning or chemical mixing areas.  Ensure that necessary traps and separators are provided for contaminated waste.  Drain to sewer or treat on site.
• Provide wash down facilities.  In particular, hose cocks incorporating backflow prevention should be provided adjacent to cooling towers and evaporative air coolers to facilitate routine cleaning and to wash down condensers in salt laden environments.
• Provide water and adequate drainage adjacent to chiller and boiler tube plates and water box drain points.
• Consider the opportunities for the reuse/recycle of waste water (bleed, condensate, pump back), maintenance water (washing, testing, and draining). Also consider using harvested water rain or reusing treated waste water.

Water treatment

Water treatment needs to be applied and maintained to keep heat exchange surfaces clean and to maximize efficiency. Water treatment is applied to control scale, corrosion, deposition, microbial growth and fouling. Water treatment is crucial for the control of microbial growth in cooling water systems. Comprehensive information on water treatment is provided in AIRAH Application Manual DA18 Water Treatment.

Specific requirements for the maintenance of water treatment systems have not been included in this application manual due to the specialised and dynamic nature of these systems. Comprehensive information on the management of water quality and the maintenance of water treatment systems is provided in AIRAH Application Manual DA 18 on Water Treatment. Water treatment may be the subject of specific legislation in your state.

Power

A power supply should be available in the plant room or near large items of equipment for the use of the service person. Where practicable, outlets should be provided inside the electrical panel of units.

Commissioning

Commissioning is the process where HVAC&R systems are documented and tested to ensure that the installed performance of the system will meet the design brief and designers’ intent.  Commissioning data generates baseline data that forms an essential part of any maintenance management program and it is essential that the commissioning data is accurate and complete.

A successful commissioning process will highlight any faults in the system design or construction, allowing them to be rectified prior to handover and operation. Commissioning data is compared with design operational requirements and the system finetuned to match the specified operating requirements. Several system tuning procedures may need to be undertaken to find the optimum settings for the system and the application.

The final performance data collected during the commissioning process is documented and this information forms the basis of any future performance based or condition-based maintenance program. Proper commissioning is essential for optimum system operation and for maximizing the benefits that maintenance can achieve for energy management, water conservation, indoor air quality and indoor environment quality.

Systems that are not commissioned fully or are not commissioned correctly will often perform poorly resulting in increased energy and water use and reduced satisfaction and sustainability. Non-commissioned systems pose a significant risk to building owners and occupants. System commissioning often uncovers problems with simultaneous heating and cooling, short cycling of HVAC equipment, underutilized control functions, inappropriate control strategy, incorrect scheduling of plant, non-compliance with regulation or design and a multitude of malfunctioning equipment and components.

Building and HVAC&R system performance rating tools contain specific requirements for system commissioning, commissioning management and system tuning. As the NCC is a design and construction document it does not explicitly require commissioning.  However, it is difficult to see how NCC compliance can be certified to the satisfaction of the building official without commissioning taking place and commissioning documentation being available as evidence.

Australian standards that relate to equipment commissioning include AS/NZS 1668.1, AS/NZS 3666.1, AS/NZS 3788 and AS/NZS 5149. The Australian and New Zealand Refrigerant handling code of practice Part 2 also provides comprehensive guidelines for the commissioning of refrigeration systems.

Comprehensive information on commissioning and commissioning management for HVAC&R systems is provided in AIRAH DA27 Building Commissioning.

Plant performance and capacity testing

Specified system requirements

At the design and specification stage, the details of any plant are often more theoretical than practical.  The developer of the property may not be fully aware of the ultimate use to which the building and plant will be put.  This would mean that the exact performance required of each individual component of plant would not be known at that time.  However, when construction approval is sought from the building authority both the performance and spatial requirements of NCC "required" plant will need to be known or conservative assumptions made.  This can be particularly difficult for shell and fit-out projects and some assumptions may need revisiting.

It is not unusual therefore for the conditions specified by the designer, who has designed to suit the owner’s initial requirements and budget, to vary from those required by the tenant or occupier of the building.  In some situations, the plant may need modification and if the plants’ performance has been required by the NCC, the modifications may need regulatory approval.  Any such modification is not the responsibility of the installation or maintenance contractor and amendments to the specified work should be at the cost of the owner or the tenant, depending on the terms of the lease.

Plant capacity issues can arise at any time during the life of the building, when the building has changed use or owner, when the requirements of the tenant have changed, or when a tenancy has changed.

If the change to requirements occurs during the warranty period, it is usual for the owner to discuss the requirements with the original designer and for the modifications to take the form of a variation under the direction of the designer again subject to any required regulatory approval.

If the change occurs after all warranties have finished and the original designer is no longer involved in the project, then the owner should treat the work as a new contract as neither the designer nor the installation contractor would have contractual responsibility for the work.  The contractor, engaged for this work, should negotiate with the owner and the owner should be informed of any restrictions to the system performance by the modified requirements.

The maintenance contractor should not be expected to accept responsibility for the provision of performance beyond the specified capacity of the equipment.

Designed system requirements

The designer will have prepared a design based on a brief given by the project developer or owner.

From these detailed requirements the designer will have analysed the structure of the building or facility and the purpose for which it is to be used and decided on the capacity of the plant required.  It is common for spare capacity to be allowed in items of the plant which may be difficult to upgrade at a later date.  Therefore, it is important that the contractor installs plant to the specified capacity. If this is not done the contractor may become responsible for the replacement of expensive equipment should later modifications be requested because the plant proves to have insufficient capacity.

It is therefore important, at tender time, for the contractor to submit, for each item of plant, a unit which has not less than the capacity specified.  After installation the plant should be commissioned to give the performance nominated in the specification.  The commissioning test results of the plant, as installed, should be recorded to enable the long-term system performance to be properly assessed.  The responsibility for the design and performance is then the designers.  Any excess capacity, designed into the system as a whole, to anticipate future changes to the building usage will be available when required.

Sometimes however, the requirements are in the form of a performance specification, i.e., the contractor is working to an end performance and not to the performance of individual items of equipment.  In this situation the contractor becomes the designer and takes on the designers’ responsibilities.

In either situation if the owner requests a modification, such as one involving increased capacity, that cannot be achieved with the plant installed, any cost involved in the changes required are the responsibility of the owner.

In a fully specified project the designer may request performance testing of major items of equipment.  The designer would expect the system to achieve the specified conditions required by the plant as a whole and will have nominated conditions required by the original design brief.  It is therefore usual to have conditions specified for separate and definable areas of the building to meet specific needs.  The contractor should ensure that these specified requirements are met at the time of the performance tests.

Operating requirements

The conditions to be maintained during system operation will have been set during the design. After occupancy, or due to some change in the use of the building, the owner may determine that the operating conditions, as set, need to be changed.  This is not a problem provided that the new conditions are within the capacity of the plant. All responsible parties concerned should be advised of the changes.

This point is important as different people may be changing control settings unaware that the settings are also being altered by some other person. It is most important that a record is kept of all alterations, including who authorised the change and the date on which the change was made. This record should be kept in an accessible location available for reference by all authorised staff.

Where a building's classification is changed, or the building's use is changed, such as a Class 6 restaurant without a fresh air economy cycle becoming a Class 6 shop which, under the NCC, may need a fresh air economy cycle, then a new building approval will be needed.

Performance capacity of equipment

It is important that each piece of equipment is tested to the specified capacity to satisfy the performance required by the system design.  In addition, each item should be tested to ensure that the performance achieves the level nominated by the designer and guaranteed by the manufacturer.

Testing to satisfy these criteria will ensure that there are no faults with the plant as supplied to the owner and that the items can be called on to give that performance when required.

It is accepted that some items of plant are modified to suit a particular installation and, although the manufacturer may claim a performance in excess of that specified, it is not possible to achieve that performance under the installed configuration. A simple illustration of this situation may be a fan, where the speed has been set for the designed requirements.

Defects liability period

When plant is handed over at the end of a construction program it will be subject to a Defects Liability Period (DLP), usually 12 months. Commissioning and maintenance are closely coupled during the defects liability and warranty period with the benefits of proactive energy efficiency based maintenance well documented.

Statutory maintenance requirements typically include the requirement to validate that the system continues to provide the performance levels achieved for the original certificate of occupancy.  Maintenance needs to be building- and system-specific as well as regulatory jurisdiction specific, different requirements apply to different buildings in different places.

The original commissioning work method statements and commissioning records for these systems should form the basis of these ongoing maintenance inspections and tests.

Warranty agreements

Responsibility for all breakdown repairs and rectification work during the defects liability period falls to the installing contractor. Components of the system will usually be subject to a manufacturer’s warranty which may be for a period different to the DLP. It is important to differentiate between warranty and defects liability, and ensure that the installing contractor provides details of all extended warranties prior to the end of the DLP.

It is also important that the installing contractor provides scheduled maintenance during the DLP as the intervention of other service providers may cloud the issues of responsibility and the failure to carry out scheduled maintenance may void warranties. Many owners misunderstand this and assume that the warranty is a maintenance program. It is essential that an engineer or contractor explains the difference between a manufacturer’s warranty intervention, a contractor’s DLP intervention and maintenance. It is important to ensure that any maintenance activities required to meet statutory obligations such as essential services maintenance is included in DLP maintenance arrangements noting that this will include a level of reporting not usually required or provided under warranty maintenance.

It is essential that a maintenance agreement be prepared beforehand and executed as soon as the plant is put into operation. Warranty work is usually the responsibility of the installing contractor to arrange and to have executed. It is sensible to enter into a maintenance agreement with that contractor until the end of the DLP.  It should be noted that some equipment may have a warranty period which expires prior to the end of the DLP. This may be due to the actual installation date being well before practical completion. Fault rectification remains the responsibility of the installing contractor regardless of warranty provisions. The life of this maintenance agreement will give the owner time to assess the longer-term requirements for maintenance management, refer Section 4.

The maintenance required during the defects liability period and that required for the ongoing service of the plant may be different and this should be made clear at the time of the preparation of the agreement.

Maintenance agreement

The maintenance agreement is a contract between the owner/operator of the plant and the installing contractor who is to carry out the work of maintaining the plant. It is a legal document and should clearly spell out:

• The project to which the agreement refers and the specific postal address.
• Who are the parties to the agreement?
• What is the purpose of the agreement?
• The responsibilities of each party to the agreement.
• The limits of the responsibilities of each party
• Details of the work to be carried out under the agreement.
• Date of practical completion.
• Commencement date of the defects liability period.
• Term of the defects liability period
• Performance and payment arrangements
• Date of commencement of agreement
• Proposed sub-contractors for any of the work
• Nomination of authorised representatives
• Insurance requirements

The document should be signed by both parties to the agreement, the client and the contractor.

MANAGING MAINTENANCE IN OPERATION

General

The maintenance process, Illustrated in Figure 4.1, is a generic process that assists owners, managers, and maintenance providers establish a framework for the maintenance management of HVAC&R services.

The process begins with maintenance outcomes specification, moves on to maintenance planning through maintenance implementation to maintenance reporting and maintenance performance review.

Figure 4.1 Maintenance management process

Maintenance specification

The first step in the maintenance process is the definition of maintenance objectives. Maintenance should be planned and delivered to achieve the overall objectives of the owner.

The owners’ objectives for maintenance can include:

• Return on investment
• Asset protection and enhancement
• Legal compliance
• Health and safety
• Building sustainability
• Indoor environment quality
• Risk management
• Cost limitations
• Marketing
• Corporate image.

Maintenance objectives serve as a guide to clients, maintenance managers, maintenance contractors and maintenance providers. Ideally maintenance objectives are developed into the system design brief so that they are designed and built into the HVAC&R services and the building owner can implement them through the maintenance policy.

The maintenance specification is a formal document that outlines the outcomes required from the operation and maintenance of a system or building.

The maintenance specification should be expressed in terms of asset management and life cycle costs and should state where and to what extent maintenance is required. The maintenance specification should be coordinated with any building energy management plan, water conservation plan or any building/business sustainability plan.

Maintenance specification can be developed prior to system construction so that the design can take full account of the policy. Providing a clear and appropriate maintenance specification delivers increased sustainable performance. The process of preparing the maintenance specification can educate management and help secure resources for and commitment to ongoing maintenance.

Maintenance performance standards

System performance standards

An essential task in maintenance management is to establish a baseline of system information and equipment performance including system performance standards. System performance standards or system operation standards help to define the level of maintenance appropriate and can be used in the monitoring and review of maintenance delivery and maintenance strategies. System performance standards can be used as maintenance performance standards and the data used to assess the effectiveness of the adopted maintenance regime.

System performance standards could comprise both technical and financial indicators for the building or system such as:

• Energy use and costs (kWh or $ /m²)
• System performance data (temperatures, flow rates etc.)
• Water use and costs (kL or $ /m²)
• Maintenance costs ($/m²)
• System down times (Hours/annum)
• Breakdown frequencies (Number/annum)
• Breakdown response time (minutes/event)
• Complaints received (Number/annum)
• Environmental indicators (CO₂equiv/m² per annum)
• Illness or accident frequencies (Number/annum).

Baseline system performance standards provide a reference against which to measure the effectiveness of maintenance implementation. Where system performance standards are adopted as maintenance performance standards they should be clearly outlined in the maintenance management plan.

Maintenance performance standards

It is best practice for Owner's to recognise the partnership and teamwork that must exist with HVAC&R maintainers and possibly other specialist trades such as BMCS services in order for the objectives of the maintenance program to be met.  This requires clear communication of the objectives, how they will be measured and the frequency of measurement.  Ideally, a series of lead and lag indicators will be used to guide the performance of maintenance so that there is a high probability of the objectives being achieved.

It is also a requirement of the system Owner to nominate conditions that could impact on the conduct of maintenance.  For instance, the building may have committed to maintaining WELL conditions, Green Star Performance benchmarks, net zero carbon, NABERS IEQ or other Green Lease obligations.

Table 4.1 provides a sample of lead and lag indicator measures that owners could use to target their objectives for the maintenance performance standards of a commercial building. Table 4.2 is a sample of maintenance performance standards for a commercial refrigeration application.  These are examples only and performance standards need to be individually set for systems and sites in consultation with the maintenance service provider.

Table 4.1 Commercial Building – Sample maintenance performance standards

Table 4.2 Commercial refrigeration – Sample maintenance performance standards

Monitoring maintenance performance standards

Maintenance performance standards should be monitored to ensure that maintenance is effective. Maintenance performance standards for a particular building or system can be assessed against internal baseline data but also industry standards or benchmarks. Financial indicators can also be expressed relative to business turnover.

Maintenance performance standards can be stated as targets or goals in performance-based plans and strategies.

System performance data can also indicate system compliance or a regulatory breach.

Baseline data

Baseline data is necessary to establish the performance benchmark for any particular system. Having baseline data established for a system ensures that the maintenance service provider has the necessary information to execute the service routine.

At the commencement of a new maintenance program, the system or equipment performance should be compared with the approved design and commissioning baseline data. Where the baseline data is not known, it should be established prior to setting maintenance performance standards.

Note: Commissioning data generates baseline data which would include air, water and refrigerant flows, temperatures, pressures, operating current, and control settings and interfaces, as well as energy consumption and service level provision.

Benchmarking

The purpose of benchmarking system data is to compare the operation or performance of a system with other systems in a peer group. The objective of the comparison is to establish whether the system performance achieved is above or below selected datum performance levels.

Benchmarking datum can be based on the minimum acceptable performance, an average performance or the industry best practice. Benchmarking can be carried out either internally, within a large organisation, or externally within an industry sector or globally.

One of the major difficulties when attempting to benchmark system data is ensuring that the comparisons being drawn between systems or buildings are fair and equitable. Even in similar buildings (construction and services) organisational, cultural and operational differences can have a significant effect on system performance data.

Maintenance planning

Once the maintenance objectives, policy and performance standards have been defined and the maintenance strategy and delivery model selected it is possible to develop a maintenance management plan. The maintenance management plan is essential to achieving effective and optimal outcomes.

The maintenance plan should define a structured approach to maintenance and should include the maintenance program incorporating maintenance specifications for all systems, maintenance monitoring, reporting and review procedures, system tuning procedures and performance standards.

The maintenance plan needs to be based on the following documentation:

• Asset register (See Clause 3.9.1).
• Maintenance strategy (See Section 5).
• Maintenance delivery model (See Clause 5.11).
• Operating and maintenance manual (see Clause 3.9.2).
• Commissioning data (see Clause 3.13).
• System specific performance standards (See Clause 4.3.1).
• Maintenance performance standards (See Clause 4.3.2).
• Maintenance schedules (See Appendix A).
• System specific tuning procedures (See Clause 7.2).
• System specific maintenance program (See Clause 4.5).
• Replacement parts provisioning

Maintenance program

The maintenance program should define the maintenance strategy that will be applied to particular plant including detailed maintenance schedules with instructions and specified maintenance frequencies. A maintenance program must be designed to reflect the specific equipment in the system or building. For the reasons discussed it is unlikely that any single maintenance strategy will be applicable to all of the systems within a building.

In determining a maintenance program, it is essential that every piece of plant and equipment be identified on asset register (see Clause 3.9.1). In any maintenance program detailed maintenance instructions for all HVAC&R assets need to be compiled. A routine or scheduled maintenance program could be developed from an amalgamation of all the individual maintenance schedules and instructions. Appendix A of this application manual lists the recommended maintenance schedules for common plant and equipment used in HVAC&R systems. Schedule AX shows how the various individual equipment schedules need to be cross referenced to the other schedules for a systems approach to maintenance.

Creating a scheduled maintenance program for a HVAC&R system entails compiling the maintenance instructions from each relevant equipment schedule (refer to schedules A1 to A42) and all cross-referenced schedules (refer to schedule AX) into a single maintenance program. Duplicated and irrelevant items can be deleted, and frequencies can be reviewed once the basic system is in place. Appendix B provides a step by step manual example of how a scheduled maintenance program could be developed for a hypothetical building air conditioning unit.

Maintenance implementation

Maintenance implementation means the implementation of the maintenance management plan. The selection of a maintenance strategy, the development of a maintenance program, the selection of a delivery model and a service provider, contractual arrangements and other maintenance management issues are all discussed in Section 5 of this manual.

The following are the 12 Steps to implementing a maintenance program for a building, facility or system:

Step 1 – Create an HVAC&R asset register – Each asset and sub asset is given a unique identifier on the register (See Clause 3.9.1).

Step 2 – Select a maintenance strategy – Preventative (Level C, B, A) and/or Predictive (See Clause 5.8). The selection should be informed by an assessment of risk and the maintenance objectives (See Clause 4.2).

Step 3 – Select a maintenance delivery model – In-house, scheduled, comprehensive or performance-based (See Clause 5.11).

Step 4 – Identify/collate operating and maintenance manual – All HVAC&R maintenance strategies and delivery models should be informed by the comprehensive system information included in system operating and maintenance manuals (see Clause 3.9.2).

Step 5 – Identify/collate baseline/commissioning data – Commissioning data generates baseline data that forms an essential part of any maintenance management program and it is essential that the baseline data is accurate and complete. (see Clause 3.13).

Step 6 – Document/Specify system-specific performance standards (See Clause 4.3.1).

Step 7 – Document/Specify maintenance performance standards (See Clause 4.3.2).

Step 8 – Develop maintenance schedules for preventative and predictive tasks (See Appendix A).

Step 9 – Develop system-specific optimisation procedures (See Section 7).

Step 10 – Select a service provider and agree a maintenance contract (Clause 5.11)

Step 11 – Implement the maintenance program.

Step 12 – Review the maintenance program (Clause 4.9)

Audits and surveys, system tuning procedures and maintenance for sustainability are all discussed in Section 7.

Trouble shooting

Trouble shooting procedures

In the event of an occupant complaint or monitored unsatisfactory system performance the cause should be investigated. It should be noted that symptoms of the problem may at first appear to be the cause and a systematic approach to the investigation is required.

As a first approach the following steps should be undertaken:

1. Talk to the building user regarding the specific nature of the complaint.
2. Listen to other occupants of the area.
3. Determine if original commissioning data is available.
4. Determine if maintenance records are available.
5. Review design strategy and intent.
6. Check control functions.
7. Check system and test.
8. Record actions and report results.

The provision of development of system specific troubleshooting charts can aid the trouble shooting process.

Troubleshooting Charts

Considerable labour time can be saved by the use of comprehensive troubleshooting charts. These are usually provided by equipment manufacturers. Purpose made troubleshooting charts can also be developed for the equipment making up a HVAC&R system.

Troubleshooting charts list the faults that could occur, or be foreseen, during the working life of the equipment. Although the charts provided by manufacturers are generally comprehensive, it is always possible for unforeseen faults to occur and the maintenance personnel may need to refer the problem back to the supplier.

A typical troubleshooting chart generally comprises three columns outlining symptoms, possible causes and potential remedies:

Sometimes a "verification check" step is added to reduce the possible causes down to the most probable cause.

Maintenance reporting

Maintenance reporting is required for the following purposes.

Verification for local accountability

Maintenance managers need to know what maintenance is being carried out and when.

Verification for statutory obligations

It is essential that plant is maintained in a safe operating condition and to ensure that it complies with the necessary statutory requirements.  In the event of an accident, or similar occurrence, the owner may be required, by law, to demonstrate that maintenance, to an acceptable standard, has been carried out.

Records are also required to verify maintenance provision against statutory maintenance requirements where these are in place. Complete and accurate records are required to enable annual certification and sign off against requirements.

Monitoring the maintenance policy and its effectiveness

Maintenance management entails achieving safe and reliable operation at the lowest life cycle cost consistent with the requirements and objectives of the owner.  Maintenance records provide the historical information required to enable the maintenance managers to make necessary changes to policy and practice during the life of the plant.

Observing performance trends

Monitoring system performance helps in fault diagnosis and to initiate corrective action when necessary.  Performance trends usually provide the first signs of developing trouble in the plant.  Careful monitoring of these trends may indicate early warning of possible breakdown or the requirement for plant replacement.  With this warning the maintenance manager can take the necessary action for planned service.

Tracking performance trends against maintenance activities is also an essential aspect of tuning the building systems. Tuning is an iterative process and relies on accurate and complete records for optimum outcomes.

Financial planning

The statistical information gathered on past maintenance can assist in the forecast of future maintenance and life cycle costs.

Maintenance monitoring and review

General

The maintenance process does not finish once the maintenance contract is awarded or once maintenance service providers have been appointed. Monitoring of maintenance performance must then be initiated, and the effectiveness of the maintenance policy periodically reviewed. This monitoring and review activity provides the opportunity for continuous improvement of the maintenance process.

A performance review of maintenance implementation usually occurs on two levels, a review of the maintenance system and a review of the maintenance performance. Any maintenance review should include a review meeting with the maintenance provider. It may be appropriate for the maintenance provider to report on energy and water use and identify opportunities to improve system sustainability and operation at review meetings.

Maintenance system review

In any review of the maintenance system the maintenance procedures, records and administration arrangements are audited to check that all legislated requirements are being complied with and that the maintenance implementation complies with the owners’ maintenance policy and objectives and the requirements of the maintenance contract.

Maintenance performance review

The basis of any monitoring and review system is the accurate collection of operational data (meter readings, temperature logs, energy use, etc.) and the proper interpretation of the information collected. If data profiles are trending in the wrong direction corrective actions can be adopted immediately. In particular, poorly performing HVAC&R systems may need to be tuned or recommissioned if data shows a lack of operational control or efficiency. Tracking performance trends against maintenance activities is an essential aspect of tuning the building systems. Tuning is an iterative process and relies on accurate and complete maintenance records for optimum outcomes.

An early task in the maintenance management plan is to establish baseline or benchmark system information and data. This data should be adjusted as best as possible for known variations or abnormalities within a building (e.g. partial vacancies, refurbishments, etc.) and adopted as maintenance performance standards (refer Clause 4.3). The maintenance performance review should be based on these maintenance performance standards as specified in the maintenance management plan. Comparison of the actual building performance data against the maintenance performance standards provides a tool with which to assess the effectiveness of the maintenance policy, management, strategy and delivery.

Care should be taken not to create too large a database of performance information that may become unmanageable and inefficient. For larger systems, only the nominated system key performance indicators need to be analysed in this regard.

Performance review report

Once the maintenance system and performance has been assessed it should be reported and formally reviewed. As with any review process the opportunities for continuous improvement as a result of feedback from the review should be formalized.

Figure 4.2 Maintenance review and continuous improvement

Maintenance budgeting

HVAC maintenance providers can positively contribute to how services are managed when consideration is given to how the Demand Organisation operates from a financial management perspective. To understand the protocols for making decisions on expenditure service providers must also understand how the organisation operates in terms of procurement and purchasing.

HVAC maintenance providers can help the Demand Organisation improve their financial planning and decision making on expenditure by:

• providing insight on the cost assumptions and possible sources of expenditure, and
• by aligning maintenance service plans to the Demand Organisation objectives for maintenance.

In order to fully participate as a service partner to their clients, HVAC maintenance providers need to understand the financial restrictions and operational environment under which they operate. Knowledge of the Demand Organisation’s budget, forecast timing and decision-making requirements can help the HVAC maintenance provider actively contribute to more effective budget expenditure and operational plans.

Operating Expense Budget

Any operational budget aims to be an accurate reflection of the financial resources required to implement and execute all of the operational requirements over a defined period. Most budget preparation methods, particularly evidence-based “zero-base” budgets, use cost estimates linked to specific cost obligations or outcomes. For example, individual costs for maintenance, fees or other charges are collated and developed with reference to detailed asset lists, engineering and performance standards.

To properly set an operational budget and accurately forecast future maintenance costs, there should be tangible justification for all cost assumptions. Estimated costs can be divided into several categories of expenditure:

Incremental ongoing costs are the fixed costs associated with planned maintenance for the period, with any cost variations or escalations accounted for.

Known projects or repair costs, expected to be undertaken during the budget period.

Estimated corrective maintenance costs following planned maintenance attendance.

Contingency amounts for reactive breakdown works – based on specific assumptions about expenditure rates, calculated by asset (resolving down to the component level if required) and expected failure rates/rates of callout.

Mitigation costs associated with OH&S/WHS, environmental and social factors.

Staffing costs, expected total renumeration package (including growth and bonus assumptions), any expected recruitment costs, training costs, flight/travel requirements, any other representations.

The HVAC maintenance provider can contribute to this process via their operational understanding of costs and service deliverables. This ensures that corrective and reactive expenditure is accounted for within the budget and operational planning process, helping to ensure that maintenance obligations are fully funded.

Annual maintenance expense analysis

In addition to gathering financial data on the maintenance tasks performed, the HVAC maintenance provider can also provide an understanding of the current asset condition, with accurate cost estimates for any planned maintenance work, so that this can be accounted for in the budget and operational plan.

Best practice Service Level Agreements should consider the following in terms of budget and forecasting timelines for the Demand Organisation:

• Frequency of attendance as detailed by relevant standards and codes
• Alignment with the lead/lag performance criteria detailed in the relevant standards and codes
• Alignment with annual certification timelines and anniversaries
• Peak operating periods for the Demand Organisation or other location specific activities
• Impact of seasonal conditions (where relevant – e.g. chiller annuals undertaken prior to summer and not during)

Where both parties collaborate to develop planned, corrective and reactive maintenance cost assumptions, this can help provide:

• A deeper understanding of where and on what the expense has predominately occurred.
• Knowledge of how much has been spent on a specific asset or asset class, giving an understanding on the condition or reliability.
• Insights into the effectiveness of the planned maintenance strategy and current maintenance regime for assets, and what issues may be expected in terms of life-cycle replacement.
• An ability to hold manufacturers to account for warranties and published life cycle claims.
• Fact based evidence for financial forecasting and future budget preparation.

It is therefore important that planned, corrective and reactive maintenance events are analysed regularly by the HVAC maintenance provider, and that condition reports are generated where required due to issues identified from the analysis of operational expenditure.

Future maintenance cost forecasts

HVAC maintenance providers should ensure that any budget documentation or prices submitted are accurate, and all cost assumption notes or estimates are fully documented; with specific details of how each and every cost is calculated and to what source information/document the assumption note is referencing.

Incremental accruals/costs are typically allocated on a full calendar-month basis with costs budgeted for the month in which they occur. Maintenance activities that are aligned to seasonal factors (such as scheduling chiller annual checks for pre-summer as opposed to the middle of summer) should be recorded. Specific maintenance activities that are linked to other maintenance outcomes (e.g. budgeting for chiller corrective repairs following the chiller annual service task) should also be recorded.

Additionally, a Demand Organisation may outline specific budget targets in terms of savings or growth, or some other objective that will further inform how the budget is created. Note that budgeted targets may differ from operational KPI targets. Typically, KPIs apply a stretch target to strive for the absolute best result, while the financial budget will reflect expenditure and needs to ensure that key expenses are not under-budgeted.

Capital expenditure

Due to the strategic nature and limited availability of capital funds, financial decision makers require a strong business case and clear understanding of why they are being asked to replace an asset. This is particularly true when maintenance regimes have been procured on the basis of extending the asset life-cycle.

Standard annual budgeting and financial forecasting processes do not necessarily capture the long-term nature of a particular HVAC&R asset’s lifecycle, including a changing maintenance profile as the asset ages.

Any review of the application of capital expenditure for an asset needs to include a strategic review of the associated maintenance records, condition reports, expense records, trend data and projected working life, which should be used to formulate and Asset Life Cycle Plan.

HVAC maintenance providers that participate in developing Asset Life Cycle Plans for the short (current year), medium (out to 5 years) and long term (the full life-cycle of the asset) are able to help justify these decisions for the Demand Organisation. Asset Life Cycle Plans can help Demand Organisations deliver a balanced capital expenditure strategy that maximises operational lifespan but not at the expense of diminished outcomes.

Asset Life Cycle planning

Where developed, Asset Life Cycle Plans work for the benefit of both parties and should be used as the main review tool for the Demand Organisation and HVAC provider to project and plan the asset capital replacement strategy for individual or any combination of assets.

Examples of service-related outcomes that can be generated from this process could be the deferral of an asset replacement due to longer life expectation following an adjustment to the planned maintenance program for the asset.

In the absence of any client formatting or submission requirements the following protocols should be used in Asset Life Cycle Plans to ensure consistency:

• Asset Information – type, model, serial number, date of install, condition
• Maintenance regime and service history including condition and corrective/reactive maintenance.
• Replacement strategy, scope of works required, and date / time of year works are planned to be undertaken, number and type of contractors required to complete the task
• Why the works need to be undertaken and what could occur if the works are not undertaken (risks associated with inaction)
• What could occur during the works (risks associated with action)
• How the works are to be managed, including impacts of the works
• Any projected efficiency benefits, sustainability outcomes or potential for income generation
• Details of any maintenance-monitoring or implementation strategy that mitigates future faults / replacement
• Any other works that could be undertaken at the same time

Aligning maintenance scope to objectives and budget

Scoping HVAC&R maintenance

The first step in scoping maintenance is for the Demand Organisation to develop a HVAC&R services asset list to be included in the program, preferably with a criticality risk rating, see Clause 5.9.

All Assets and equipment to be included in the scope of work should be reviewed in accordance with the following:

• Condition of the asset
• Life expectancy of the asset
• Opportunity to update, replace or modernise to provide more effective outcomes or long-term cost savings
• Availability of spare of standby assets/equipment
• Current expenditure on Planned Maintenance for the asset

Maintenance specifications and the associated scope of work should document a detailed listing of tasks to be performed for each asset or item included in the Planned Maintenance program. Any basic performance requirements should be designed to ensure that planned maintenance items are reducing or mitigating the requirement for reactive/corrective maintenance.

Other factors that could impact the scope of a maintenance agreement would include:

• Culture, including relationships with other suppliers and requirements to cooperate/coordinate
• Survey and inspection requirements - review of asset data provided and update any discrepancies found
• Site access, plant access and system isolation protocols
• Spare parts and materials requirements
• Site housekeeping requirements

A current list of all Assets included in the planned maintenance program should be maintained and include:

• Make, model, year, and manufacturer recommended service schedule.
• The dates and details of all non-scheduled major machine repair.
• Dates of service from previous maintenance tasks
• Data from Building Information Modelling (only data that is useful for the Demand Organisation)

Maintenance objectives

The Demand Organisation should work with the HVAC&R maintenance provider to clearly outline the desired outcomes for the planned maintenance regime. The potential objectives for maintenance are discussed in Clause 4.2. There may be different objectives for different HVAC&R assets.

From the perspective of the Demand Organisation, HVAC&R Maintenance can play a significant role in supporting the operation of plant and systems that are identified as critical to their business or operation, see Clause 5.9.  Critical systems could include cooling systems serving a data centre, telecommunications or IT facility, lift motor room, HVAC systems serving office areas, or refrigeration systems preserving food or medical products.

There are a number of factors that need to be nominated by the Demand Organisation to ensure that service level maintenance agreements deliver outcomes that are aligned to the objectives of the organisation. These factors include the:

• Strategic objectives of the organisation
• Regulations and compliance standards
• Criticality/risk of HVAC&R services to the core business of the organisation
• Maintenance and operational culture of the organisation
• Sustainability objectives, conditions and commitments e.g. NABERS rating, WELL conditions, green lease obligations, net zero carbon certification
• Coordination requirements with any Energy Management Plan, Water Conservation Plan or general Sustainability Plan
• Protocols on the use of technology and data or CMMS system

For a performance based arrangement there needs to be a clear communication of objectives, how they are measured and frequency of measurement, preferably nominating Lead and Lag indicators of performance, see Clause 4.3.

Aligning maintenance strategies with objectives

The Demand organisation and HVAC&R maintenance provider need to discuss and agree on the maintenance strategies that are needed to meet the agreed objectives. This may include a mix of strategies targeted at a range of different HVAC&R assets, see Clause 5.8.

Strategic considerations include:

• Prescriptive or performance maintenance standard – task versus outcome focus
• Frequency and conditions of Planned Maintenance
• Provision of Service Reports and format
• Protocols regarding corrective or reactive works identified during service
• Agreement on terms of reference and priority rating
• Tag out protocols for defective equipment until repaired
• Reporting and account management arrangements

Compliance maintenance should be discussed and agreed between the Demand Organisation and the HVAC maintenance provider based on the Asset Register (or HVAC&R asset sub-list) and relevant legislative and regulatory requirements. Compliance maintenance tasks and frequencies should be clearly defined to meet the requirements of the applicable legislation, any compliance standard and also the Demand Organisation needs and objectives.

MAINTENANCE STRATEGIES

Maintenance strategies defined

There are some elements of maintenance that are not discretionary. They are tasks, mandated by codes or regulations to ensure the safety and wellbeing of building occupants, service personnel and the public, that need to be included in every maintenance plan.

Other maintenance actions or tasks are determined by the performance criteria (see Clause 4.3) that may include efficiency, reliability, equipment life and maintenance costs. No single strategy will suit all equipment in a given facility. The most appropriate strategy should be selected for each plant item and system.

The two main approaches to maintenance can be described as proactive maintenance or reactive maintenance.

• Proactive maintenance – which includes a range of maintenance strategies for maintenance delivery including preventative and predictive maintenance techniques:

Preventative maintenance (PM) strategies – which includes:

1. • • Scheduled maintenance, for example: replace a filter every 3 months or test a fire damper once every 5 years
     • Repair/Replace on condition, for example: replace the filter when the differential pressure across the filter exceeds 200 Pa

Predictive maintenance (PdM) strategies – which includes:

1. • • Data driven analytics,
     • Condition monitoring, and
     • Reliability centred maintenance

A tailored maintenance program for a building or plant is typically a hybrid, incorporating elements of scheduled maintenance, system monitoring and metering, plant condition monitoring and predictive analytics or fault detection and diagnosis.

2. Reactive maintenance (RM) – which is the principle of run-to-failure, and then repair or replace individual physical components. Reactive maintenance is also called “Operate to fail” or “Breakdown maintenance” and is really the absence of an ongoing maintenance strategy.  An example would be running the system until the filter is so blocked that air conditioning fails to perform and then change the filter to re-establish operation.

Breakdown maintenance is also required when the HVAC&R system fails to deliver to the owner’s specified requirements.  For instance, failure to maintain temperature in an air conditioned zone may not be caused by a physical failure of a specific component but through the interaction of a number of system elements including software.  Regardless, this breakdown requires maintenance to ensure performance can be restored.

Preventative Maintenance (PM) strategies

Preventative maintenance (PM) strategies include:

• Scheduled maintenance, and
• Repair/Replace on condition,

Scheduled maintenance

Scheduled maintenance comprise a list of pre-determined maintenance activities that are delivered at a specified frequency. Scheduled maintenance can include all the mandatory tasks required under regulations, tasks required to ensure ongoing health and safety, tasks identified by the equipment manufacturer, tasks required to ensure ongoing system sustainability and those accepted as normal practice.

An example of scheduled maintenance is the regular servicing of a motor vehicle. Service is carried out on the recommendation of the manufacturer based on a fixed distance travelled or an elapsed time, whichever occurs first. Industrial maintenance is often scheduled on elapsed operating hours.

Under a time based or scheduled maintenance strategy; overhauls of plant are performed at periodic intervals.  The timing of the maintenance activity will ideally be calculated to minimise the combined planned and emergency repair costs. The majority of failures can be pre-empted, although some will still occur.  The results of a poorly designed maintenance schedule can be that much of the work performed is unnecessary, and some may even introduce failures into healthy plant.

An approach to developing a scheduled maintenance program for a system, building or facility is provided in Appendix A. Three ‘levels’ of maintenance are provided in the schedules:

• Best Practice
• Good Practice
• Compliance 

All maintenance programs must incorporate the tasks and frequencies nominated for compliance level (C) and then select either;

• Good Practice (B), as the base level for a general good practice HVAC&R maintenance solution; or
• Best Practice (A), as the best practice approach for reliability and energy performance management.

Figure 5.1 Layout of a typical maintenance schedule

Maintenance schedules for plant and equipment commonly found in HVAC&R systems are provided in Appendix A. A basic scheduled maintenance program can be developed from compiling these individual schedules into a system program. A step by step example of this process is provided in Appendix B.

Schedule format

Three ‘levels’ of scheduled maintenance are provided within the maintenance schedules (see Figure 5.1):

Level A)      Best Practice – this includes all of the maintenance tasks and frequencies to comply with the compliance and good practice levels outlined below and would typically include for some tasks to be scheduled more frequently to ensure greater knowledge and understanding about plant condition, or suggest where additional proactive information may be continuously gathered to increase vigilance or analyse trends, such as vibration analysis, thermograph, etc.

Level B)      Good Practice – this includes all of the maintenance tasks and frequencies to comply with the compliance level outlined below and the additional work required to achieve a good scheduled maintenance program. This level is particularly important for equipment that does not have compliance requirements such as pumps, and therefore if left to Level C alone would not have a structured maintenance program. This level is a good industry-practice level however, it is somewhat discretionary as there is no ACT or Regulation requiring this work to be performed.

Level C)      Compliance – this is the minimum maintenance standard required to meet statutory compliance. incorporating the requirements from the regulations, plus obligations to environment, health and safety and general duty of care. Compliance maintenance requirements are based on the maintenance compliance standards AS 1851, AS 3666.2/.3 and AS/NZS 5149.4. Statutory requirements in individual jurisdictions vary and should be checked to determine local requirements.

Schedule Frequencies and Tolerances

The reporting frequencies described in this application manual are suggested only. Actual frequencies should be determined by the owner, or owner's representative, either by specification or by consultation with the servicing contractor and equipment supplier. System designers should provide comprehensive recommendations on maintenance actions and frequencies within the system operating and maintenance manual. Maintenance frequencies must be appropriate to the specific application and take account of the conditions of use.

The frequencies selected will depend on factors such as

• Type and technology of equipment installed.
• Operating environment.
• Geographical location.
• Intensity of use of the equipment.
• Priority given for the equipment to remain operational.
• Seasonal operation profile.

For reasons of practicality and flexibility a time tolerance for frequency should be specified. Recommended tolerances are set out in Table 5.1.

Table 5.1       Time tolerance for service frequencies

Such tolerances are not applicable where specific statutory requirements or specific owner instructions state otherwise.

Maintenance frequencies should be kept under review. A possible indication of the need for more frequent maintenance could be a repeating failure profile. Maintenance frequencies can be extended if supported by long-term maintenance records and experience or by the application of condition monitoring procedures.

Repair/Replace on condition

This strategy is a simple version of condition monitoring. Equipment is inspected regularly, but intervention only occurs according to levels of wear or other indicators.

An example of this strategy is the maintenance of tyres on a motor vehicle. The tyres are inspected at scheduled services. If abnormal wear is detected, then a tyre rotation and front wheel alignment may be carried out. As tyres near the end of their service life they are inspected more often to ensure continued safety whilst achieving maximum life.

Predictive maintenance (PdM) strategies

Predictive maintenance (PdM) strategies include:

• Data driven analytics,
• Condition monitoring, and
• Reliability centred maintenance 

Data driven analytics

In the data-driven analytic approach to predictive maintenance the physical condition, performance, or efficiency of a system is evaluated by monitoring selected digital input data and comparing the actual data received against a defined baseline. Any variance in the two datasets is used to identify the appropriate maintenance intervention. Using a combination of digital monitoring and analytical software algorithms this process can be automated to a large extent, providing both continuous monitoring and alarm, as well as automated detection and diagnosis.

Data driven analytics is becoming a much more achievable maintenance strategy for many owners because the rapid digitisation of the sector and technology has reduced costs and technical barriers and made the application of the strategy much more accessible.

Refer to Section 6 for further information.

Condition monitoring

Condition monitoring uses advanced techniques to assess the condition and performance of components so that optimum equipment performance can be sustained. There are many condition monitoring techniques, all with varying levels of applicability to the HVAC&R industry.

The important issues when applying condition monitoring are:

• Always obtain base readings early in the life of the equipment. It is far easier to interpret changes over time than it is a single assessment.
• Undertake monitoring on a regular basis and plot trends.
• Always attempt to get a high signal to noise ratio for the measured variable. Background vibration, for example, can often mask results.
• Always measure at fixed reference points.
• Remove all other variables. As far as possible reset loads and operating conditions to be the same for each measurement.

Once the results have been reviewed maintenance actions are initiated by trends highlighted by routine or continuous monitoring of the equipment.

Condition monitoring for a system or item of plant may be scheduled, continuous or by request. Condition monitoring can be more expensive than other strategies, but there are situations where unplanned down time cannot be accepted under any circumstances.  In these situations, the owner/user has to accept the higher cost of the service contract.  On the other hand, reactive maintenance, while being less expensive in terms of contracted maintenance costs, can be surprisingly expensive if a failure that could have been prevented by carrying out a relatively easy repair causes the total loss of a piece of equipment.

Refer to Section 6 for further information. The following is a list of the most common condition-based monitoring techniques:

Visual, aural and tactile inspection

This is the simplest form of condition monitoring and is also the basis of the repair on condition strategy. Many problems are detected by simple inspection, or with optical aids to assist viewing internal components.

Monitoring of process parameters

Performance is often a good indicator of the condition of a machine and can be assessed by monitoring its process parameters, e.g. temperature, pressure, flow rate, etc. Building energy management systems provide an ideal vehicle for the collection and analysis of this information.

Vibration analysis

Out of balance forces can be particularly destructive and increase wear by orders of magnitude. These forces are identified by the amplitude of a vibration signal. The frequency of vibration signals is particularly effective for identifying faults such as cracks and flats in rolling element bearings. It is particularly important to establish base line values and fixed measurement points for vibration analysis

Infra-red techniques

This is a non-contact technique which measures the temperature of an object on the basis of the infra-red radiation received from its surface. It is particularly suited to surveying electrical systems. The simplest devices measure the temperature at a single point whilst thermo-graphic imaging cameras can record an image over an area. It applications in HVAC&R extend to detecting heat leaks in pipework, ductwork and the exterior of buildings.

Lubricant analysis

The condition of lubricants can be analysed to determine its remaining service life ensuring that it is not replaced prematurely or too frequently. More importantly contaminants such as moisture, dirt and wear particles can indicate impending component failure or the need to change the equipment operating conditions. This technique can be effective for slow moving or difficult to interpret, reciprocating or complex machines where vibration analysis may be more difficult to utilise.

Leak detection

Methods from “soap and water” to ultrasonic and tracer gas techniques can detect minute leaks. This is an essential technique where ozone depleting and high global warming potential refrigerants or toxic gasses are still in use.

Corrosion monitoring

Corrosion is the greatest enemy of plant and equipment. Early intervention to correct the problem can extend plant life dramatically. Electrical resistance and potential techniques, hydrogen detection, sacrificial coupon and bore holes can all be used to detect and assess the extent of corrosion.

Crack detection

Many non-destructive testing methods are available for crack detection. These include dye penetration, flux testing and ultrasonics. Cracks often precede catastrophic failure of a component. Cracks in components such as castings can be halted by drilling a hole at the root of the crack to relieve stress or by welding them up.

Electric current monitoring

Frequency spectrum analysis can be used to detect a number of faults on electric motors including broken rotor bars, static and/or dynamic air gap irregularities, and mechanical imbalance.

Continuous bearing condition monitoring

Critical plant items such as return air/smoke-spill fan motors may be the subject of continuous bearing condition monitoring as an alternative to scheduled or adhoc analysis. In continuous bearing condition monitoring, vibration and temperature data can be communicated to (and analysed by) the Building Management System aiding in the early detection of required maintenance and faults.

Reliability centred maintenance (RCM)

This maintenance strategy incorporates elements of the other strategies, but sets itself apart, mainly through a process called a Failure Mode, Cause and Effect Analysis (FMCEA). As the name implies each element is analysed to estimate its effective service life and to determine indicators for identifying impending failure.

Categories of equipment often exhibit similar failure profiles over time. Electronic components generally follow a ‘bath tub’ profile (see Figure 5.2) in which there is a high level of failure on start-up, then a long period of reliable service followed by a large number of failures as components age. This curve is empirical and can be applied to many systems and plant that are subject to wear and tear.

Figure 5.2 “Bath-tub” failure profile

An example of an RCM initiated maintenance procedure would be lighting replacement in large offices which is best done in bulk when the lamps are nearing the end of their predicted life. Labour costs are reduced and disruption to the office is minimised.

Reliability centred maintenance has the potential to reduce the cost and increase the effectiveness of building services maintenance but must be applied appropriately. Experience in the HVAC&R industry has taught us that FMECA is difficult to apply, particularly to refrigeration equipment.

This equipment is manufactured to close tolerances and the internal components operate in an ultra-clean environment. They are thus very reliable. The failure of a component such as reed valve would be identified as a mode of failure, but the frequency of failure would be very low. Age and manufacturing defects would be the identified causes. System failure would be the effect. In this case predictive maintenance has no advantage over assessment on age.

Predictive Vs Preventative maintenance

Although both predictive and preventative maintenance strategies are intent on achieving the same outcome, i.e. extending the life of equipment and preventing unexpected breakdowns, they have a very different approach.

Preventative Maintenance (PM), is carried out using specific tasks, (such as those covered by the schedules in this manual), on a calendar date or time/usage basis, to reduce plant lifecycle costs and improve efficiency.

Predictive Maintenance (PdM), leverages technology to directly, and continuously, monitor performance against a set of baseline data, and attempts to predict when key maintenance or repair activities need to take place. Some form of digitals condition monitoring system or data analytics system must be in place to provide this data.

Understanding the additional efficiencies that can be achieved with PdM, is best shown by the Performance vs Failure Curve, see Figure 5.3. This represents the typical behaviour of an HVAC&R asset, such as a pump or fan, prior to a total failure occurring.

With PdM, detecting a failure event earlier means that there is more time to plan for any required works, or resolving problems that can be fixed with minor corrections prior to more intensive interventions being required.

Figure 5.3 Performance vs Failure Curve

There are several key assessments that need to be made in order to review whether a PdM strategy is the right way to go for any given asset, with the hierarchy as below:

Safety – What are the potential impacts on personnel, the asset, the building or the environment in the event of a total failure.

Asset Criticality – How critical to the business processes is it that the asset keep operating functionally, and what is the hourly impact on downtime.

Spare part availability.

Current maintenance costs -  the cost of deploying a technical solution in lieu of preventative maintenance, after reviewing the above steps.

Such assessments are key to establishing a priority around assets, and prioritisation is key to understanding the return on investment (ROI) from maintenance implementation.

Incorporating PdM into PM

Incorporating predictive maintenance strategies into a planned maintenance schedule can be as straight forward as cross referencing what tasks are provided for in greater frequency and accuracy by use of a digital solution rather than a time based one. Looking at Schedule A22 for fans for example, task Items 2, 3, 4, and 7 can potentially be carried out by a CMS system, monitoring continuously, which is at a higher frequency than once per month.

Reactive maintenance strategy

Under this strategy, equipment is given no maintenance and is repaired or replaced when it ceases to perform its required function. This approach cannot be applied to systems that have a safety, health, or environmental compliance requirement.

Work is only performed to remedy failures, which have occurred.  As no action is being taken to prevent failure, the failure rate may be high.  For some equipment this will incur high repair costs.  The availability of plant will also suffer leading to high business losses in critical applications.

This is normally applied to minor equipment that can be readily replaced or plant that has little strategic importance to the business or facility. An example may be a simple zone temperature sensor that on failure would have a low consequence as long as a replacement can be found and installed promptly.

The risks associated with this strategy are high. Both predictive and preventative maintenance are superior forms of maintenance because they provide an active risk control measure.

Good practice Vs best practice maintenance

The selection of a maintenance approach is ultimately based on the maintenance outcomes required by the client or demand organisation.

Table 5.2 summarises the characteristics that differentiate between the different approaches to maintenance; Reactive, Compliance, Good Practice and Best Practice.

Table 5.2 Characteristics of HVAC&R maintenance

Selecting a maintenance strategy

There are times, or situations, where each of these maintenance strategies are appropriate.  It is incumbent on the installing contractor and the system designer to make the owner/user aware of the probable costs in, and advantages and disadvantages of, all of the alternative maintenance strategies available and to recommend the most appropriate strategy for the particular system or building.

Ultimately it is the owners responsibility to nominate a maintenance strategy and this needs to be consistent with the objectives for the maintenance program and the available resources and maintenance budget.

Many owners elect to use a performance-based maintenance program, as this will give them a degree of reliability at a rate which is acceptable in terms of the overall plant cost and acceptable down time. This can be achieved through selectively integrating condition-based techniques with the traditional time based and breakdown maintenance strategies in a mixed approach. At system level, the importance will vary with the system function so whilst condition-based maintenance may be justifiable for an air handling unit serving computer equipment, it is unlikely to be justifiable for a toilet ventilation system.

A performance-based maintenance regime applies an optimum mix of different approaches, based on risk, costs and consequences. Establishing the appropriate mix and focusing on continuous improvement are equally important in a performance-based maintenance strategy.

Figure 5.4 Example of a possible maintenance strategy selection decision process

Risk assessment for strategy selection

Risk assessment techniques can be used to assist in the selection of the most appropriate maintenance strategy for each application.  Understanding the likelihood and consequence of equipment or system failure allows resources to be directed to those activities that have the greatest impact on the operational success of the facility.

More detailed information on using risk assessments is included in appendix D.

Identifying critical areas and services

Maintenance can play a significant role in supporting the operation of plant and systems that are identified as critical. This includes plant that serves areas or processes that are critical to the business or facility and plant or systems that may have high risks associated with them.

Identification of critical services

The most obvious systems that can be identified as critical are those systems and plant serving areas or processes that are deemed essential to the performance of the enterprise. Obvious examples include cooling and air conditioning systems serving critical data centre, telecommunications and information processing functions, or mechanical and HVAC plant and systems serving critical areas in acute care hospitals such as Operating Theatres and intensive care areas. Less obvious examples can include air conditioning systems serving lift motor rooms or PABX/communications rooms in commercial buildings.

Identification of high risk services and equipment

Some HVAC&R services also have risks associated with their operation or presence. Examples include kitchen exhaust systems which may present a fire risk to the building, due to grease build-up in the duct, or refrigeration and air conditioning plant that contains large quantities of refrigerant, that could leak into a confined area. Many of these high risk systems will have compliance standards that should be applied but enhanced maintenance is a good way to mitigate these risks.

Example of maintenance strategy selection for systems

Design review

In addressing the risk of system and or plant failure and its potential impacts, the design of these systems should be reviewed for operational redundancy and single points of failure. In this review the issue of repair and or replacement risk should also be addressed. Sometimes the criticality of systems and plant is exacerbated because repair or replacement is difficult or likely to be prolonged because of replacement plant or parts availability, access or other logistics issues.

Ideally unacceptable operational system and plant risks can be adequately addressed by design changes, adding in redundancy or other risk elimination or mitigation factors. All systems and plant serving critical functions should supported by appropriate maintenance and asset management regimes.

Enhanced maintenance

In some circumstances this may not be possible or practical to reduce system and plant operational risks by changing design. Enhanced maintenance regimes may be implemented to improve the effective reliably and availability of critical plant. In many instances this may also increase the technical and economic life span. These regimes should be developed based on a sound understanding of the failure modes for these systems and plant, and the opportunity for avoidance of failure by early identification and intervention.

Enhanced maintenance regimes can include:

• Increased frequency and or stringency of inspection and review to provide greater of surety of pre-emptive discovery of problems.
• Increased frequency of intervention; checking, calibration, testing, adjustment, lubrication
• Increased frequency of replacement of key components subject to wear and or failure; bearings, sensors, belts and drives, seals and glands, lubricants and filters,
• Holding of key spare parts, design and replacement related documentation
• Enhanced instrumentation; vibration, temperature, pressure - data logging and analysis, including the use of IoT devices, and applying data analytics techniques to system operational data provide predictive information or early warning.

Figure 5.5 outlines a systematic process for identifying and managing HVAC&R critical areas and services.

Identify Enterprise Critical areas or processes

ê

Identify systems and plant that serve these areas and any subsidiary systems and plant these depend on

ê

Review systems for design opportunities to remove or reduce the risks associated with single points of failure or lack of system redundancy

ê

Review systems for issues of repair or replacement risk

ê

Review failure modes of systems and plant

ê

Identify opportunity to better ensure system and or plant performance with enhanced maintenance regime including opportunities for instrumentation

ê

Develop and implement enhanced maintenance regime

Figure 5.5 Identifying critical areas and services

Cost/benefit analysis in strategy selection

Maintenance strategies can also be selected by comparing the costs and benefits of each applicable strategy in order to achieve the lowest lifecycle cost.  More information on cost/benefit analysis is provided in Appendix E.

Maintenance delivery models

The four recognized delivery models for HVAC&R systems maintenance are:

1. In-house maintenance delivery.
2. Scheduled maintenance contract.
3. Comprehensive maintenance contract.
4. Performance based maintenance contract.

In-house maintenance delivery

There are two models for in-house maintenance delivery:

1. For large installations or multiple sites, it may be economical to employ a team of technicians to deliver the service. Such teams exhibit a ‘critical mass’, whereby at least two resources are required for each trade category in order to cover leave and other absences. Savings made by owning staff may be eroded by the need to employ temporary staff at premium rates
2. Companies with a maintenance capability associated with their core business may utilise those resources to maintain peripheral plant such as HVAC&R. This can be effective for routine work, but complex tasks may still require the services of external resources. For this model to work the team requires excess capacity to ensure that the core business is fully serviced, and the peripheral maintenance is not neglected. The maintenance budget can easily increase as small problems can absorb excessive hours and non-essential minor works can be hidden from the balance sheet.

Both of these models suffer from the fact that the technicians may not be specialists in the field so that their ability to identify and correct faults in a timely manner is often compromised. Specialist can be called in at premium rates.

Scheduled maintenance contract

Under a scheduled maintenance contract, maintenance is delivered by a specialist service provider. Specific maintenance tasks are defined and delivered on a mixture of time based and usage-based criteria. Repairs are carried out externally to the contract and may be performed on a ‘do and charge’ basis or by quotation for each repair.

‘Do and charge repairs’ are normally based on agreed hourly labour rates and a fixed mark-up on materials. For quoted work, it is normal for an estimate to be accepted for small jobs and fixed quotations for larger jobs. For larger repairs, demand organisations will often seek quotations from several sources.

The advantages of a scheduled maintenance contract are:

• The work to be undertaken is clearly defined.
• The demand organisation is involved in controlling costs.
• The financial risk to the contractor is minimised.
• The client can invest in strategies to prolong equipment life.

Comprehensive contract

In a comprehensive contract the service provider agrees to undertake the scheduled maintenance plus any repairs.

The major advantages of a comprehensive contract are that the client has a fixed amount to budget for maintenance and doesn’t need to make decisions regarding repairs. The client pays a premium for this as the service provider takes a substantial amount of risk on the cost of repairs.

Performance-based contract

A performance-based contract is aimed at using the service providers’ expertise to tailor maintenance to achieve the operational outcomes required by the client. The concept is one of ‘partnering’, allowing the client to operate at peak efficiency and the contactor to achieve economies by better controlling the amount of maintenance work required

A performance-based maintenance delivery model requires a longer-term commitment from both parties as significant effort is required to get the processes matched to the outcomes.

Selection of service providers

The selection of service provider is the key to satisfactory maintenance, which will result in reliable plant performance, good plant life and reasonable expenditure. Lowest tender price is the least appropriate way to select a service provider. Value for money should be the determining factor. The ideal situation is where the demand organisation and service provider establish a partnering relationship, recognizing that the service provider needs to make a profit and the client needs to contain the costs.

A potential service provider should have the following attributes:

• Competent, committed and well-trained technicians.
• Appropriate licenses, insurances and accreditation.
• Appropriate level of resources.
• Efficient and accurate maintenance management system.
• Informative reporting system.
• Accurate and timely invoicing.
• Economical and reliable after-hours service.
• Quality, environmental and safety management systems.

The assessment of maintenance contractors should include an evaluation of their sustainability practices. The environmental footprint of maintenance service providers, their energy and water use, their transport arrangements, their paper use, their reclamation and recycling policy and the like should be considered.

Preparing maintenance contracts

In preparing a maintenance contract it is essential that the documentation is clear, concise and readily understood by both parties. A well-prepared contract offers protection to both the contractor and the owner/tenant. While a standard form cannot be specified, a survey of some contracts presently in use indicates that the following items are generally covered in the body of most service contracts:

• A description of the systems, and a list of equipment and accessories.
• The scope of work to be carried out by the service contractor and a time schedule.
• The extent of the contractor’s guarantee in connection with the work to be carried out.
• The effective dates and the time period of the contract.
• The amounts and terms of payment.
• The responsibilities of each party to the agreement.
• The limits of the responsibilities of each party.
• Proposed sub-contractors for any of the work.
• Nomination of authorised representatives.
• Insurance requirements.
• The conditions for termination of the contract, by either party.
• Any other general conditions which may cover contractual responsibility, or to ensure compliance with current legislation.
• The names of the contracting parties and provision for signatures and, if necessary, company seals.

It is important to include a list of owner/tenant responsibilities in addition to the provisions for payment. An example of this is:

The Owner/Tenant agrees to:

•        Designate a representative to receive instructions in the operation of the equipment. This representative to have authority to carry out instructions received from the contractor to fulfil the terms of the agreement.

•        Operate the equipment in accordance with the contractor’s instructions, and to notify contractor promptly of any change in the usual operating conditions.

•        Keep the equipment rooms and space free of all extraneous materials and to facilitate the work called for under the agreement.

•        Employ only persons acceptable to the contractor to operate or adjust the plant and equipment.

At all times it is important that the terms and conditions of the service contract should be fair and reasonable to both parties.

The contractor also has a duty to properly report to the owner/tenant prior to entering the site for routine work. The contractor should also report before leaving the site so that the owner/tenant is fully conversant with the progress of the work.

Scope of works

The scope of work must make it clear whether any or all of the following maintenance services are required:

• Operation of plant.
• Maintenance only.
• Repair of plant.
• Component replacement.
• Plant replacement.
• Record keeping and compliance management.
• System documentation updating (O&M manuals, drawings).
• Energy monitoring and management.
• Water monitoring and management.
• Call out and emergency work.
• Ongoing audit and assessment.

Insurances

Insurance is always specified in the contract and the types of insurances that may be required include:

• Public liability
• Professional indemnity
• Employers’ liability.
• Workers compensation.
• Third party personal and property damage
• Consequential losses (i.e. due to breakdowns etc.)

There is also the question of plant insurance to cover the effects of catastrophic failure of critical plant and equipment.

Maintenance records

Maintenance records have moved almost totally to electronic data stored in Computerised Maintenance Management Systems (CMMS). Some remain paper based, particularly mandatory site log books for essential services. Paper based handwritten records need to be legible. WEB based systems are in place for many services, providing a high degree of transparency and attendant reporting.

Included in this section is a selection of report forms, which could be distributed physically or accessed electronically. They can be used as a guide to the information which should be included on reports by maintenance contractors to indicate to the owner that the work of the inspection and maintenance has been carried out in accordance with the maintenance agreement. These forms are not intended to cover every possible situation but are intended as a guide to a suggested layout and an indication of how the report forms may be prepared.

The maintenance contractor and the owner should discuss the information required as a simple certificate advising that the work has been carried may suffice. In this case the owner relies on the contractors recording systems to provide detailed information should the need arise. Some owners may require a copy of the maintenance schedule included with the report, with completed items individually noted. Two examples of how the reports may be set out are covered in the following:

Maintenance staff

In selecting maintenance staff, the most important criterion is matching the individual to the necessary tasks. Skills shortages within the HVAC&R service industry mean that staff are in high demand and will move between employers or contracts to obtain satisfying work, with good conditions and remuneration.

The employer requires good productivity from staff in order to remain competitive and profitable. This requires staff to be focused on their work, execute it promptly, identify and document faults accurately and repair them effectively.

The client expects quality workmanship, reliable plant operation, prompt attention and value for money. Above all else, clear and accurate advice on the state of play will ensure customer loyalty.

There are many maintenance tasks which do not require a high level of skill, but rather require attention to detail to ensure a simple task is done properly. Examples being filter cleaning or changing and greasing of bearings. These can be carried out by trained personnel under the supervision of a qualified technician.

Effective maintenance of more complicated equipment goes beyond the technician knowing the actions they are required to take. They must understand why those actions are required. An understanding of system design is essential for senior technicians. Accurate record keeping, and well documented plant performance data underpins maintenance efficiency

The ideal maintenance person has:

• Well-developed trade skills, accompanied by the appropriate qualifications and licenses.
• Good written and oral communication skills.
• Thorough knowledge and understanding of applicable codes and legislation.
• Awareness of and empathy with sustainability issues.
• Pride in their workmanship.
• A flexible attitude to working hours.
• Commitment to both the client and the service company.
• A thirst for knowledge.
• Pride in their appearance.

Maintenance staff safety

Maintenance personnel require a range of certifications and licenses to carry out the required maintenance work on HVAC&R systems particularly in respect to refrigerant handling, boiler work, water treatment and electrical work. Many of these licenses relate to safety issues.

Maintenance personnel need to be informed of any risks and the appropriate work practices. For example, service personnel who carry out maintenance on cooling towers should be advised of the risk of Legionella and the proper use of all personal protective equipment as well as the hazards associated with the chemicals used for disinfection and cleaning.

Situations where the safety of maintenance personnel needs to be carefully considered include but are not limited to:

• Working in confined spaces and at heights
• Refrigerant handling (toxic and flammable refrigerants)
• Water treatment chemicals
• Cooling water systems
• Boilers and pressure vessels
• Inflammable liquids
• Electrical work.

Maintenance personnel should be appropriately trained in first aid and any applicable emergency procedures.

Workplace hazards are not always obvious, they may be concealed or be not readily visible, they may develop over time and some hazards may be temporary or intermittent. Service personnel may not be familiar with the site or workplace which can present a further hazard. (See also AS 1470 and AS/NZS 4801)

Safety risk management

To properly identify and manage exposure to risk associated with hazards in the workplace the five-step risk management process should be followed:

1. Identify hazards
2. Assess the risk
3. Decide on control measures
4. Put control measures in place
5. Review the control measures

Control measures should be implemented in the following hierarchy:

1. Remove the hazard
2. Reduce the hazard
3. Separate the hazard from people
4. Engineering measures
5. Administrative measures
6. Personal protective equipment

Detailed information on risk assessment and risk management is provided in Appendix D.

Personal protective equipment

Personal protective equipment (PPE) is clothing or equipment designed to be worn by someone to protect them from risks of injury or illness.

PPE should only be considered as a control measure when exposure to a risk cannot be minimised in another way, or when used in conjunction with other control measures as a final barrier between the worker and the hazard. PPE does not control the hazard at the source.

Make sure that:

• PPE is used in accordance with the manufacturers’ instructions
• the PPE fits correctly
• workers are instructed and trained in how to use and maintain it
• Appropriate signs are displayed to initiate PPE use.

SMART MAINTENANCE

Introduction

A lot of maintenance procedure is about information; generating data, comparing information, recording results. Managing information flows lends itself well to digitisation.

Advances in digital technologies provide opportunities for more advanced maintenance services and solutions. Time analytics pulled from big data, relayed by wireless sensor networks, analysed by cloud-based algorithms and visualised on mobile computing devices, are changing maintenance, disrupting traditional practices and creating new value opportunities.

Information technology in maintenance helps us to:

• understand system operation and performance
• make efficient use of sensor information
• provide system history
• identify when systems are failing and how to repair them

This section outlines the main ways that information technology can be leveraged to generate improved maintenance outcomes. The first step is to address inter-communication between devices and systems.

Standardising digital information

As HVAC&R maintenance move to digital platforms, understanding how to shift from paper- or simple file-based asset management, to digitally hosted and aggregated management platforms such as a CMMS (Computerised Maintenance Management System), becomes essential. How this initial information set or database is created and maintained, the quality of it and the language protocols used, is an important element for its effective operation.

Several initiatives have been growing in the industry that assist with promoting a common format or “language” for the way IoT data and BIM data is transferred within and between systems and devices:

• Dynamic, or IoT Data (e.g. from sensors and controllers)– Project Haystack; (www.project-haystack.org). Project Haystack is an open source initiative to streamline working with data from the Internet of Things. The objective is to standardize semantic data models and web services with the goal of making it easier to unlock value from the vast quantity of data being generated by the smart devices that permeate our homes, buildings, factories, and cities. Applications include automation, control, energy, HVAC, lighting, and other environmental systems.
• Static, or Asset Technical Data (e.g. from BIM, Building Information Modelling) – COBie: (www.bim.natspec.org). Construction Operations Building Information Exchange (COBie) is an international standard relating to managed asset information including space and equipment. It is closely associated with BIM approaches to design, construction and management of built assets. COBie helps capture and record important project data at the point of origin, including equipment lists, product data sheets, warranties, spare parts lists, and maintenance schedules. This information is essential to support operations, maintenance and asset management once the built asset is in service.

Digitisation of maintenance management

Smart maintenance includes using digital and IT technology to inform and drive plant and system maintenance. By capturing, analysing and reporting on plant and system performance, smart maintenance systems can:

• maximise the efficiency of the maintenance workforce,
• minimise the plant and system failure frequency and
• optimise the plant and system operation.

Smart maintenance must deliver customer value. Smart maintenance systems can be designed to give users a real-time view of their maintenance needs, so they can make informed decisions.  Collected data must be used effectively to improve both plant and system efficiency and customer satisfaction.

Computer maintenance management systems (CMMS) can be regarded as a necessary component of a smart building. Implementing complex CMMS solutions beyond the end user’s wants, needs or capability, can be counterproductive.

Computerised Maintenance Management Systems

Information is at the heart of a successful maintenance management system. Depending on the complexity of the building and systems the volume of maintenance information required for maintenance management can be large and many organisations make use of computer-based systems for managing it.

There are many proprietary computer maintenance management systems (CMMS) available on the market, some specifically designed for HVAC&R system maintenance. Systems can be either web-based or on a local area network. CMMS can help maintenance managers and service technicians increase the availability of HVAC&R systems and reduce maintenance costs and repair times as well as reducing parts supply time and increasing parts availability by improving supply chain communication.

The management of CMMS software, firmware and hardware needs to be in line with an organisation's corporate policy on computing hardware and software. The attributes of these packages need to be assessed for cost effectiveness. While many are very comprehensive there is little value in purchasing a system having an abundance of features that cannot be effectively utilised. A typical CMMS package deals with some or all of the following:

• Asset management – Recording data about equipment and property including specifications, warranty information, service contracts, spare parts, purchase date, expected lifetime, etc. Capital works project management.
• Scheduled maintenance – Keeping track of maintenance inspections and actions, including step-by-step instructions or check-lists, lists of materials required, and other pertinent details for preventive maintenance (PM) schedules and maintenance task scheduling.
• Logistics – Scheduling jobs, work orders, assigning personnel, reserving materials, recording costs, and tracking relevant information such as the cause of the problem (if any), downtime involved (if any), and recommendations for future action
• Inventory control – Management of spare parts, tools, and other materials including the reservation of materials for particular jobs, recording where materials are stored, determining when more materials should be purchased, tracking shipment receipts, and taking inventory.
• Safety – Site safety management. Management of permits, licenses and other documentation required for the processing of safety requirements.
• Document management – Including CAD/BIM capability;
• Reporting – Status reports and documents giving details or summaries of maintenance activities, invoice information. Reliability data

Importantly for HVAC field service providers the cloud-based CMMS systems are relatively site agnostic, meaning they can be used remotely for multi-site support by third party providers.

Cloud based CMMS solutions

The best-of-breed cloud centric smart maintenance solutions utilise big data capability to enable dynamic predictive maintenance programs to be managed according to failure frequency and the identified business risk factors for individual systems, rather than on a generic or asset class basis.

A new breed of cloud-based IoT centric CMMS is emerging built around the following basic hardware and communications structure:

Digital controls and controllers

Direct Digital Control (DDC) systems are built into machines that communicate to a BMCS through dedicated cabling or an ethernet network using protocols such as BACnet, Modbus and LonWorks.

Sensors collect data from machines or the environment, actuators can change the physical conditions developed by the plant.  Sensors can monitor temperature, humidity, air pressure, energy use, voltages, currents, vibration, GPS coordinates, occupancy and a host of other factors. Sensors can be linked to a BMCS or directly to internet gateways.

Wireless sensor communication systems are beginning to replace hard wired systems, and there are a number of short-range and long-range communication protocols in use.

The recent introduction of Low Power Wide Area Network (LPWAN) sensors that allow direct communication through mobile phone networks to the internet is particularly useful for connecting sensors and remote plant to the cloud. Prominent LPWAN communication protocols include LoRaWan, NB-IoT and SigFox.

Internet Gateway/ Edge IT

Gateways poll analogue data from sensors and BMCS, process the data, then dispatch the data by ethernet, Wi-Fi or GPS to the cloud-based data centre. Non-GPS connectivity is preferred due to the ongoing cost of mobile plans.

Edge IT computing can be in the gateway or a separate Edge processor to optimise data transfer to the data centre, for example real-time data is not dispatched unless the information is mission critical, or unnecessary data is not sent over an expensive GPS network. Edge IT also provides additional capabilities such as onsite analysis and security protection.

Data Centre and Cloud

System management and detail analysis (AI, ML etc), graphical displays, dashboards and reporting are undertaken in the data centre, this can be done on site or in the cloud.

Note: Cloud-based solutions require good internet or mobile connectivity when working remotely, particularly where mission critical tasks are involved. Internet connectivity isn’t always available in remote locations, basements or underground. Even if your cloud-based solution can work offline you will probably still need to download data from the internet

Building management and control systems (BMCS)

A Building management and control system (BMCS) is a high-end control system which performs the overall control, monitoring and reporting for some or all of the building plant or systems.  They are also referred to as building management systems (BMS), building automation systems (BAS), and building automation and control systems (BACS).

A BMCS consists of a number of digital controllers which communicate via a network infrastructure and report to a computer referred to as a head end, supervisor or operator workstation.  The function of the operator workstation is to send operational parameters to the controllers, such as set points and time schedules.  Conversely, the controllers can send operational information to the operator workstation such as temperatures, alarms and system performance information.

The controllers are digital and operate with embedded software which has been developed specifically for HVAC control known as direct digital control (DDC).  The software has incumbent control algorithms or logic, which can perform a multitude of tasks when configured in a sequence.  Configuration of the DDC software is known as control logic, control sequences, or simply code. 

BMCS system design and development are specialist areas and close liaison between the system designer, system installer, system commissioner and BMCS system provider is essential. Because of the interoperability afforded by open standards, BMCSs are capable of providing integration, including connectivity, monitoring, and control. These apply not only to the HVAC system but also to such other systems as:

• lighting controls
• access controls and security
• closed circuit television systems
• power management
• elevator systems

Maintenance management systems can be integrated with energy management, water management, other building services systems and emergency management within the BMCS to provide a fully integrated control and management system.

The functionality of a BMCS stops short of the control of essential systems such as standby power generators and building safety systems such as fire control or smoke management systems.  Where a BMCS might share information across its network to provide control variables, essential systems use local information and hard-wired interlocks for reliability and resilience.  A BMCS may monitor the status of the essential services plant to provide reports and alarms to the operator workstation.

Automated energy management systems (EMS)

Energy management is a process for which software-based control technology is ideally suited, particularly when implemented in conjunction with operating and maintenance management. Integrated data analysis allows complex reporting and analysis to be presented in simple format on screen or by graphs, charts and spreadsheets that can be printed out on request or routinely as required.

The automated energy and maintenance management system has the potential to perform many functions, including:

• Operation of all plant to minimise energy consumption while optimising environmental conditions.
• Continuous monitoring of all plant to detect faults and institute corrective action.
• Control of necessary timing of particular portions of plant for diversified operation.
• Use of automatic maximum demand logic control to predict and minimise energy demands on the total plant.
• Establishment and upkeep of an energy management plant maintenance system to cater for periodic inspection and servicing of all systems and to monitor maintenance problems associated with individual items of equipment.

As an example of the benefit of automation in both energy and maintenance costs, modern chillers are generally reliable and run for long periods with very little maintenance attention. However, gradual deterioration of the performance does occur due to fouling of tubes, refrigerant leakage or controls drifting out of calibration. These all lead to an increase in energy consumption and, if not attended to, result in the machine failing to meet peak load or, eventually, a breakdown. Parameters such as water temperatures and pressures at the chiller can be readily monitored by a software-based system, predictions can be made about expected trends, and decisions on chiller shutdown for servicing made such that inconvenience and call-out costs are minimal.

Digitisation of maintenance delivery

Internet, mobile and wireless technologies

Service personnel need to be mobile but they also:

• Need to collect and record data.
• Need to access system technical information.
• Need to create reports and reviews.

There is a growing application of information technology devices and systems particularly with regard to mobile and wireless technologies and remote access to internet and email.

Examples of IT application in maintenance management include practices such as:

• The use of bar coding and other plant identification methods like smart tags.
• The use of portable field devices e.g. tablet pc’s, or smart phones to capture data, produce service reports, check email, access the internet, and read bar codes or other electronic plant identification devices.
• Use of web-based reporting services (portals) to provide access to maintenance records and access to statutory maintenance records (in some states this obviates the requirement to keep on site paper statutory maintenance records).
• Access to web-based information – manufacturers’ latest maintenance recommendations, plant disassembly and assembly information, manufacturers parts lists, materials and parts price lists.

Smart Tags

Smart tags are physical objects that are fixed to an asset, to create a link between the asset’s physical and virtual representations, a digital ID tag. A smart tag could be something as simple as a barcode, or as complex as a computer chip.

Although it is possible to find a physical asset’s virtual representation or vice versa (e.g. by searching by asset type, model, location etc.), smart tags make the process much more convenient, efficient, and less error prone. The low cost of modern tagging systems makes it a very worthwhile exercise for dealing with even relatively small quantities of assets.

There are many kinds of tags that can be used. Below is a summary of some of the most common current and emerging solutions.

Printed tags

Printed tags are the legacy standard that most people are already familiar with. They are typically printed out on a label and stuck onto the physical asset. These tags have the advantage of being compatible with legacy systems and being readable by the human eye as a fall-back. However, they have the disadvantage of being more clunky to use with modern devices and being more susceptible to degradation (i.e. ink smearing, fading, covered by residue).

Barcodes

This is the same technology used to tag products at a supermarket. Historically these were read by specialized laser barcodes scanners. However, with the rise of smartphones, carrying a scanner around in the field is an unnecessary burden, and the clear winner for the sensor of choice is now the digital camera.

QR Codes

These are special type of barcode, specifically designed to be easily readable by the digital camera found in nearly every smartphone. Typically, a camera will be able to read a QR code much more easily than legacy barcodes and is the preferred method if compatibility with legacy barcode scanners is not required.

Electronic tags

RFID tags - RFID tags are small electronic devices embedded in a package that can be attached to an asset. ‘Passive’ (meaning they are powered externally), RFID tags which would typically be used for asset identification, are cheap and durable. They are powered by their antennae, with the energy being transmitted wirelessly from the scanning device. Reading the tags is as simple as moving the scanning device in range of the tag. RFID tags may also have the capacity to be written/overwritten in the field without additional hardware.

NFC tags - NFC (Near Field Communication) tags are technically a specific type of RFID tags. The main benefit of using NFC is it being the de facto standard for compatibility with smartphones. The majority of new smartphones have NFC reading/writing capabilities built-in, and those that do not can be extended to support it. Passive NFC tags are very cheap per unit, and arguably provide the most convenience for asset identification.

Diagnostic and handheld tools

There are a range of handheld electronic meters and diagnostic tools available to the service technician, auditor or surveyor. These include:

• Airflow meters
• Temperature and humidity meters
• Particle counters
• Carbon dioxide meters
• Carbon monoxide meters
• Cable testers
• Calibrators
• Clamp meters
• Data loggers
• Humidity meters
• Infrared thermometers
• Light meters
• Mixed gas meters
• Pressure meters
• Refrigerant leak detectors
• Sound level meters
• Multi-meters
• Oil and fluid analysers
• Thermal imagers
• Temperature probes
• Torque meters
• Gas probes
• Vibration meters

The use of these tools promotes rapid diagnosis of plant problems and facilitates the regular checking of system operating parameters and set points. Many of these tools and systems can download collected/recorded system data direct to a PC or other portable device.

Diagnostic and handheld tools should be recalibrated regularly to ensure accuracy of results.

Smart schedules

The use of paper-based or spreadsheet maintenance schedules in the field is being replaced by electronic forms (e-forms or smart schedules) that can deliver significant productivity gains. The benefits of creating electronic forms or smart schedules for maintenance work can include:

• Increased productivity in the field – with reduced paperwork and electronic reporting, the field technician can do more in less time, no double data entry and deciphering hand writing, form results can be dispatched from the job to the responsible persons;
• Better management of specified workflow procedures - e-forms can be structured to expose the workflow in the most logical and economic order, where the required tasks are only exposed as they need to be executed, and to facilitate real time workflow task tracking and job efficiency analytical tools;
• Enhanced problem-solving capability - e-forms can link to the manufacturer’s maintenance manual; service histories can be called up; works orders can be automatically logged from the e-form; calculations can be automated on the e-form;
• A more professional customer service offering enhanced visibility – Loading of the e-form results onto online portals and dashboards, mean the data is immediately available in the cloud, and the client gets to see the real value of the service provided;
• Data acquisition and maintenance/compliance -when properly configured e-forms can promote integration with CMMSs, FMSs, BMSs and other computerised management systems;
• Integrated health and safety management - systems can be set up so that a maintenance job cannot be commenced until the mandatory JSA or SWMS form has been completed;
• Making future changes to an e-form is simple, and no paper waste is generated when form changes are implemented;
• Eliminates physical storage – incorporating e-forms eliminates much or all of the need for printing and storing paper forms.

Normal backup and cyber security protocols should be applied.

The potential negative aspects of maintenance e-forms can be:

• Loss of connectivity - choose an e-form solution that works offline with the data uploading to the cloud when the device next syncs.
• Battery life limitations – generally not a problem with modern high-quality smart devices, backup power packs are readily available.
• Field technician resistance to change – a diminishing problem as younger more digitally aware staff enter the industry. Best practise is to commence the roll-out of the new technology with the more digitally aware staff and/or to partner these staff with staff that may be less comfortable with digital innovation.

Digitisation of Asset Management

BIM asset data to FM maintenance database

The considerable amount of data which is created during the design, development, construction and commissioning of the built asset, if properly configured and integrated, can be harnessed to create a digital asset to drive value, and cut costs and waste in operation. This data-driven digital asset can provide a dynamic platform on which to manage present and future maintenance.

BIM to Building Information Management

Building information models created during the design, manufacture and installation of an HVAC&R system contain a range of information that can be leveraged into asset management. The opportunities are great but there are also barriers.

Unlike drawing formats like CAD, even 3D CAD, BIM is a database. When an asset is added to a BIM file it brings with it a dataset about that asset.  In the case of an HVAC asset, such as a ventilation fan, that data is not only about what model fan it is and where the fan is physically located, but also what the is connected to (mechanically and electrically), the methods of construction and materials used, warranty and safety information, and manufacturers contact details.

The quality and effective downstream use of this data has become the focus for many working with BIM, and for the HVAC&R industry the lead initiative is BIM-MEP-AUS, (www.bimmepaus.com.au), which seeks to standardise the content and quality of BIM data across all products. Extending the BIM datasets to include HVAC&R asset commissioning data, lifecycle information and service data is a key part of this initiative. This facilitates what were once disparate files, to now reside in a common database which can provide ongoing operational value for the life of the facility.

BIM to CMMS

Another emerging trend is the integration of CMMS with BIMs. Recognising the importance of the BIM database in the evolution of information management, CMMS providers are creating ways to integrate with it to extract the asset information as a foundation for their own database. Given that typically 80%-90% of a building’s total lifecycle costs are operational rather than capital, if the building asset has a BIM it makes sense that the CMMS is integrated with the BIM database.

Due to the quality of the data, some applications provide “viewers” to navigate the 3D visualizations to allow operators to see the asset within the context of the facility.

No matter how extensive and integrated the CMMS system is with the BIM database, both need to be maintained and aligned. The CMMS database should not supersede or make the BIM database redundant, as this will lead to other functionality and efficiency losses over the life of the facility.

Protecting maintenance information and data

IoT – Overview

This digital life of a product starts with the digital design and analysis of the components, passes on through a digitally controlled manufacturing and assembly process, leading to the digital monitoring of the product in operation, often for maintenance purposes.

Cybersecurity

As the digital landscape expands, and the collection, use and collaboration on data concerning a facility increases, all parties need to evaluate the security and protection of this data, and understand the possible vulnerability of sensitive information that may be exposed if safeguards are not in place. Although security policies and standards regarding digital transformation in the Construction and facilities management environments in Australia have been slow in development, there is still the overarching Privacy Act 1988 and cross border data protection to consider when managing this issue.

There are three important questions to be answered when creating or managing an information management plan:

At every stage of the data’s lifecycle - who is the responsible organization under the Act?

At every point in the data workflow - where is the data stored, and does it cross any international borders?

At every data manipulation stage - How do we ensure the continued validity and/or quality of the data?

Information Management Plan

Having an Information Management Plan, with security management at its core, becomes an important step in understanding what is happening with any data concerning the facility. The expectation should be that this will be an evolving plan, as adoption of various data strategies come into play, start at a basic level and progress over time. security strategies should be part software or computational, and part user awareness with access control and threat protection.

NOTE: A good practice reference guide to cybersecurity and digital asset management is PAS1192-5:2015

Data Storage

The type and location of data storage will usually depend on the solution that best serves the facility management in terms of IT policies, suppliers and collaboration required, but will initially fall into two groups:

On Premise – (Onsite) – Where the data collection, and any corresponding software applications reside on an internal company network. This usually offers higher levels of security, due to limited exposure to the internet and IT policies being in existence to protect sensitive business data but can come at the expense of access to external third-party IoT devices, and third-party provider collaboration.

Off Premise – (Offsite) – Where the data collection, and any corresponding software applications reside in an external data centre, normally termed “Cloud” technology. This allows higher levels of integration and collaboration, but questions should be asked regarding the security and workflows provided.

Data Acquisition

Data acquisition covers the collection of multiple data sources, and depending on the information sources, may have multiple paths or technologies in use, for example:

Wi-Fi

4G

ADSL

Satellite

With any of the data transport types used, it is essential to ask what cyber-physical systems are in place to protect the data, and who is responsible for its implementation, review and action.

Data ownership

Because data is a commodity, the general industry consensus is that, the data is owned by the purchaser, but the IP regarding the systems and software used to aggregate and analyse the data, remain the property of the vendor, though this should be clarified contractually on a case by case basis.

Contractual Safeguards

Having an information management plan in place is key to understanding each parties’ roles and responsibilities, along with expected outcomes in terms of security, demarcation, validity, access and ownership. Scope and contract documents should be reviewed on a regular basis to ensure that they remain relevant and encompass any new tasks and roles.

Monitoring and metering HVAC&R

Predictive Maintenance (PdM) can leverage digital technology to directly, and continuously, automatically monitor system or plant performance against a set of baseline data, and predict when key maintenance or repair activities need to take place. The system needs baseline and real-time data to operate and some form of condition monitoring data analytics system must be in place to provide this data.

Digital monitoring systems

HVAC equipment such as fans, pumps, motors, boilers, and chillers are computer-designed/optimised and are manufactured to very close tolerances enabling better operation and performance. These system components are more efficient and reliable than they used to be, but they are also more reliant on correct maintenance.

Remote monitoring and predictive maintenance play an important role in capturing the value of digitisation for a system owner.  Before the advent of digital monitoring systems, service staff had to manually measure and adjust airflow, temperature, and other aspects of the HVAC&R system. For speed and efficiency, individuals performing these tasks cannot compete with modern digital systems.

Predictive maintenance uses captured information to schedule the ideal maintenance interventions. Remote sensors collect and report data on the condition of the plant and the performance of the system. Based on this data:

• early indicators of equipment problems are detected for timely correction at minimal costs, maintenance resources can be prioritised and optimised,
• system downtime is reduced and
• plant operating life is increased.

In digital management of HVAC&R performance, advanced analytics and cloud computing are used to improve maintenance scheduling. The data collected is used to generate highly specific maintenance plans that account for the actual usage patterns of the target systems.

The basis of all digital approaches to system management and maintenance is the digital monitoring system.

Developing a digital monitoring system

To effectively design a monitoring system for HVAC&R control and management you need a good knowledge of the HVAC&R theory at play as well as detailed knowledge of the system design intent so that the correct

Digital monitoring systems capture time series data of specified system operating variables and control points. These parameters can include energy use (overall and individual equipment), temperatures, flow rates, pressures, weather conditions, equipment runtime and status, actuator positions and control setpoints.

The parameters and operating variables specified for the monitoring system should represent key performance indicators (KPI) for the systems covered. The information to monitor in a HVAC&R system includes those characteristics that indicate system performance.

The design of HVAC&R monitoring systems need to consider:

• how sensors and data is identified to systems
• what data is to be monitored
• how the data is to be recorded
• the resolution or sampling rate
• time synchronisation of all data
• downloading and formatting protocols (relating to the communication protocols of the various devices)
• data analysis method.

The level of monitoring can be quite detailed.

Monitoring HVAC&R provides the following opportunities:

• Operational data – providing snapshot data and medium and long-term trends of key system performance data.
• Analytics – Allows the comparison of real-time data to history and rules-based algorithms providing fault detection, alarm and system optimisation
• Alarming and notification – Alarms set up in a system serve as a trigger for digital or human intervention
• Reporting – The data generated by a monitoring system can be converted into customized reports for billing and management purposes

Data for a monitoring system

Data sources to be monitored in a HVAC&R system include:

• Temperature
• Flow
• Pressure
• Moisture/Enthalpy
• Power
• Motor speed
• Vibration

Information to be monitored in a HVAC&R system include:

• Position of valves and dampers
• Setpoints and control points
• Data trends over time

Big data or smart (targeted) data

There is a lot of talk about ‘Big Data’ in the industry but what does it really mean?

Big data generally means the collection and storage (and analysis) of large amounts of data, the bigger the data set the better for meta-analysis. For HVAC&R maintenance however, having targeted meaningful data is much more important than the volume of data recorded.

In a typical building it is not generally beneficial to collect every data point possible, only selected points are required.  There can be hundreds of thousands of data points in a building and it is often a waste of resources to collect everything.

‘Smart data’ can still be ‘Big Data’ but instead of collecting everything only target points are collected and stored for future use or analysis.

Data to target

With more and more data being generated it is important not to get carried away with the collection of it. The collection of all inputs and outputs of a control system is extremely important and should always be performed. An example of data that could be collected includes:

• Energy Consumption
• Sensor readings
• Actuator positions
• Motor Speeds
• Motor Enable/Status

It’s also important to collect ‘Control’ points such as set points, schedules and after hours calls.

Compression of raw data to selected characteristic values

Cleaning and validating data

Metering

Metering of HVAC

Metering of HVAC systems is undertaken for a range of deliverables, most commonly for energy management and billing purposes (leased tenancy or cost centre allocations). The extent of metering is dependent on the application and therefore designers need to clearly state the intent of the metering system.

In addition to energy management and billing a metering system may be used for:

• Oversight of BMCS operation
• HVAC system tuning
• Measurement and verification (M&V) of energy savings
• Leak detection (some thermal meters include leak detection)
• Accurate data for NABERS or Green Star ratings

Metering is often required for a number of services delivered by different trades. Metered systems include electricity, gas, potable water, recirculating domestic hot water, HVAC thermal, solar output, recycled water and waste water. Close co-ordination of metering system delivery is necessary as all reportable data may be required via a single platform.

Metering and management

The effective energy management of HVAC will require the installation of an electrical metering system but may include water (make-up) and fuel (gas or diesel oil) metering. Many types of meters are compatible with DDC systems and where possible meter data should always be made available to the control system.

The metering of plant room water, fuel and electrical inputs and thermal and energy outputs enables the calculation of system COP. Benchmarking COP for energy management across a range of load and ambient conditions facilitates effective, on-going performance monitoring. Start up and operational control strategies can be finely tuned. When combined with thermal storage, system demand and efficiency can be tailored to provide lowest cost operation.

Metering system design

The overall intent of the metering system must be clearly understood prior to determining specific metering requirements. The type of metering required for energy management differs to that required for billing or other management purposes. The main thermal plant should be metered such that each type of equipment (chillers, cooling towers, pumps, etc.) is electrically metered. There is no need to meter each motor individually.

Cost effective metering is often dependent on the switchboard layout. Ideally, each equipment type will be co-located in a single section together with the meter for that equipment type. Equipment not associated with thermal output, such as extraction system control and power distribution, should be separately located and metered.

All data should be recorded on the same time base, typically no lower than 5 minutes or no longer than 30 minutes.

Automated fault detection and diagnosis systems

With the amount of data being generated by systems today it can be beneficial to use software for the automated detection and analysis of operational faults within the system being monitored. These software platforms run monitored data through a set of algorithms to automatically detect and diagnose faults within the HVAC&R systems.

A distinction exists between:

• platforms that can ‘detect’ faults, this can often be performed within the BMCS (trends and alarms); and
• platforms that can perform the ‘Automated Diagnoses’ of faults (to initiate a response).

Automated fault detection and diagnosis (AFDD) systems can ‘diagnose’ the root cause of the issue and help to initiate corrective action, all automatically.

Fault detection rules

Fault detection has traditionally been performed by the BMCS or DDC in the form of ‘Alarms’.

The primary function of fault detection rules is to test monitored data against known fault conditions to alert the end user. These rules are very basic and typically pickup items like; failed temperature sensors, equipment motor mismatches, no airflow readings, etc. These fault detection rules give very little insight to the root cause of individual faults and only alert the user to a problem for further investigation.

Fault diagnosis algorithms

Fault diagnoses algorithms expend further on fault detection rules and help pin-point the cause of an issue. These algorithms first detect a fault and then interrogate the data/system further to attempt to diagnose the cause of the issue.

For example, taking a typical fault detection output such as ‘VAV box not registering an airflow’, there is no indication if this is a failure locally at the VAV box, or further upstream at an isolation damper or air handling unit. Fault diagnoses algorithms can take all of the relevant system data into consideration to pin point where the most likely cause of the fault is.

The use of fault diagnoses algorithms reduces the amount of time spent investigating the cause of issues and streamlines the maintenance delivery process.

Cloud Software as a Service (SaaS)

Software as a Service (SaaS) is a software licencing model where the software platform is hosted in a remote centralised location (Cloud Servers). The SaaS model is becoming more prevalent in HVAC&R and has many benefits, for example:

• Data redundancy is provided
• No server maintenance is required
• Updates are rolled out automatically

The SaaS model has it disadvantages too. As a licencing model it typically requires a monthly/yearly fee to keep the software active instead of a one-off payment for a local solution. The Cloud SaaS model also relies on the end-user IT polices allowing external access to the networks within the building, this can be a problem for secure sites and often is not a suitable model for this reason.

Condition Monitoring Systems

Condition Monitoring Techniques

A Condition Monitoring System (CMS) is a specialised monitoring system that monitors specific operating data or characteristics with regards to determining the “health” of certain types of equipment.  Within the HVAC&R industry, this generally refers to the four main types of digital monitoring techniques used for the generation of CMS data sets which are:

• Vibration monitoring
• Ultrasound detection
• Electrical Signature Analysis
• Temperature monitoring

These techniques can be incorporated into a wider preventative maintenance plan or schedule, to achieve earlier and more accurate fault detection, and improved operational efficiencies.

Data driven monitoring and performance analysis is another method of CMS. Some examples of the possible applications of the various CMS techniques are shown in Table 6.1.

Table 6.1 Applying CMS to components, plant and systems

Vibration Monitoring

Vibration monitoring is a system designed for assessing rotating plant and machinery, primarily the condition of the bearings, shafts, gears and mountings. It consists of a sensor known as an accelerometer, designed to measure “acceleration” in terms of a sudden change in velocity.

Most systems analyse this as millimetres per second/second, (mm/s²), or simplified as the engineering unit “G”. Measurements are taken in all three axes, horizontal, vertical and axial, the predictive diagnostics are quite complex and component specific, and should only be carried out by a competent person.

As a basic example of typical “G” values that may be seen for a fan:

• Excellent = Usually 0.10 G or Less.
• Good = Usually 0.30 G or Less.
• Fair = Usually 0.50 G or Less.
• Rough = Usually 0.75 G or More.
• Very Rough = Usually 1.00 G or More.
• Danger = Usually 1.50 G or More.
• Breakdown Level = Usually 2.50 G or More, shutdown and repair.

If unusual noise or temperature is present, then the G levels become secondary. They are to be used as an analytical guide only.

Ultrasound detection

Ultrasound detection, via early spike or stethoscope, has been applied as a front-line preliminary predictive maintenance method for many years. The method provides ease of access to monitoring equipment and very early detection of faults. Because it has largely remained a site-based activity, it is used as a complimentary tool to vibration monitoring systems which are generally better able to leverage IoT platforms.

Electrical Signature Analysis

Electrical Signature Analysis, (ESA), is a relatively new technology used for assessing motor driven plant. It uses complex algorithms to identify both electrical and mechanical faults, by assessing the system power quality. Sometimes referred to as Motor Current Signature Analysis (MCSA), although the two techniques are different, both require testing equipment that is highly specialised, and should only be carried out by a competent person, especially because live electrical circuits are involved.

Performance Analysis

Performance Analysis is where true IoT, or big data analytics come into operation. This is where the physical efficiency, performance, or condition of a system is evaluated by comparing the actual received data against a modelled or initially tracked baseline data. The variance in the two datasets is then used to predict the optimum time to carry out maintenance works.

While performance analysis was initially used to determine the deterioration in energy performance, the accuracy of rule-based algorithms has matured enough to also enable predictions in overall plant condition, with enough historical data. See Clause 6.8 for more information on fault detection and analytics.

Baseline data profile

With the adoption of any condition based monitoring program, having an initial period of monitoring to create a default data profile or baseline data is important.  Each item of equipment will have its own operating characteristics, and it is the deviation from these baselines that a CMS system is looking to analyse. Typically, the first 2 to 3 months of monitoring is used to form the baseline data profile, during which other methods are used to check that equipment is running normally.

Performance indicators for evaluation of CMS

Performance indicators for condition monitoring systems are generally relationship-based, i.e. it is the effect CMS has on other processes that is typically measured. CMS effectiveness is not usually measured by how often the equipment has failed, instead it is measured by how well it has helped maintenance planners with scheduling for parts and labour. Some examples of how to measure if the processes have improved are:

• Planning time from fault diagnosis to repair
• Reduced unplanned work
• Reduced downtime in repair (lower lead time issues).
• Labour utilization, (productivity, overtime etc.)
• Lower WHS risks with plant failure.

Therefore, such systems are often used as the basis for predictive maintenance strategies in lieu of preventative.

Digital predictive methodology limitations

Not everything can be monitored digitally, so when creating a predictive maintenance schedule, it is important to review all tasks, ensuring that certain tasks for compliance, and any manufacturers requirements are still retained.

New digital competencies

As with the evolution of maintenance methodologies, new roles and competencies are becoming more common place within the HVAC&R industry, including:

• vibration analysts,
• data scientists (analytics), and
• higher levels of IT training for the IoT and cloud technologies now being implemented.

In recruiting, sub-contracting, or upskilling staff to cover these new roles and competencies, it is important to remember that quality and efficiency can be at risk during early adoption of any new technology or processes.

Smart Maintenance Implementation

Smart Maintenance is a digital transformation strategy based on new technologies that capture data, automate tasks, and free up human resources. Because not all maintenance functions can be digitised Smart Maintenance uses digital intelligence to reduce the number of technician site visits while delivering superior service.

Success largely depends on how this transformation is planned and implemented.

Previously desktop-based maintenance systems were relatively data poor, due to the manual nature of the data acquisition, the exception being data rich SCADA type systems.

Today’s systems are increasingly “data rich” portable cloud-centric solutions utilising web, mobile and increasingly IoT communication protocols. This means monitoring, analytics and diagnostic maintenance services can be more easily outsourced to third-party providers.

HVAC maintenance service providers continue down the digital transformation pathway, first adding smart features to legacy maintenance systems and now truly making the transformation to smart digitised maintenance systems.

Arguably the single largest impediment to making a successful digitisation transformation is the embedded culture. According to McKinsey some 70 percent of change programs fail to achieve their goals, largely due to employee resistance and lack of management support.

The key steps for implementing a Smart Maintenance strategy are:

• Planning the transformation
• Choosing the right system and functionality
• Implementing a system
• Managing the culture change
• Leveraging the business benefits

Planning the transformation

Plan your digital transformation strategy carefully. Evaluate your workflows and question each activity:

• Working with your team and clients identify where the inefficiencies are in the legacy systems.
• Map your customer needs against the new Smart Maintenance digital technologies to identify how they can generate the data needed to deliver a superior customer service.
• Working on a “whole to the part” basis scope out the Smart Maintenance solution.
• Plan your digital transformation pathway to efficiently make the migration from your legacy maintenance system to the new Smart Maintenance system including managing the changes in the culture of your organisation.

Choosing digital systems and functionality

The choice of which digital systems to choose depends largely on the feature and functionality set required.

There are many CMMS solutions in the market, careful due diligence is required when selecting the right solution, matching the system functionality to the operators needs and capabilities. Typical system features available are listed in the CMMS section above.

In the future it is difficult to see any state-of-the-art CMMS solution not incorporating AI and IoT capabilities. Other emerging technologies that will become standard features include  augmented reality (AR) and virtual reality (VR).

The database and analytics package should be designed to cater for digital data aggregated from both the legacy and Smart Maintenance systems, as well as associated non-digitised data relating to the assets that are being serviced. The database must be backed by a robust analytics and reporting system that demonstrates that real value for money is being delivered to the client.

One of the greatest challenges facing the maintenance service industry is clients not valuing the services provided, the services have low visibility leading to customers question value for money and an expectation for cheaper low value service levels.

Implementing a system

Never lose sight of the key objectives of the digital transformation process and never surrender control of the change process.

Start with small steps. An early challenge is to upskill people to work with both the legacy and the new Smart Maintenance solutions while the underlying digital transformation proceeds.

Initially most of the servicing will be for the existing network of older machines from which the data will continue to be acquired manually or semi-manually by technicians in the field, a “pull” solution. The legacy maintenance system may incorporate smart technologies, such as mobilised field services, but still not be delivering a holistic “Smart Maintenance” solution.

As “smart” machines are installed into the network the focus will incrementally move to the use of smart technologies where sensors, gateways and edge IT “push” the data into the cloud where it is analysed and acted on by AI technologies.

Managing the culture change

When implementing digital transformation never underestimate the difficulties in changing an existing culture. People are loyal to culture, not strategy, when culture and strategy clash culture will almost invariably win.

Digital transformation delivers significant changes to people’s work processes, changes to the familiar legacy systems that have typically built-up over many years and are embedded in the businesses culture. The automation of many maintenance tasks through digital transformation is highly disruptive. It may intimidate people who are uncomfortable with technology and may cause workforce push-back against the increased visibility of workplace performance that digitisation also provides.

A key element for a successful digital transformation implementation is fostering a culture that promotes technological innovation while investing in staff development by upskilling and improving workplace conditions.

Empower people by engaging them in the planning; hold regular feedback sessions; set reasonable expectations; acknowledge that there will be problems and frustrations along the way; deal with genuine issues promptly; identify digital champions; mobilise early adaptors first; provide excellent training; highlight what has worked and celebrate successes; these and other common-sense strategies will collectively ensure the success of the digital transformation process. 

Acknowledge that a primary reason for the digital transformation is to improve productivity and profit but stress the significant benefits for staff who embrace the digital transformation process.  Be firm with resistors and work out ways to get them on board. But if this proves impossible, consider reassigning or replacing them.

Digital transformation is device centric, consider having policies in your employment contracts covering the use of digital devices, particularly if you intend to use GPS tracking. The privacy of employees has to be protected, particularly if the employee owns the mobile device.

Business benefits

The HVAC&R service industry is facing a shortage of the qualified field technicians needed to meet the increasing demand for services and replace retiring staff. A successful digital transformation process makes a business more competitive when competing for available talent, particularly with the younger generation who are often more comfortable with technology and less concerned about privacy than previous generations.

Businesses that successfully implement a digital transformation process, including a well-structured training and advancement strategy, will be seen by technically able prospective employees as a more attractive place to work than businesses that don’t. 

CONTINUOUS IMPROVEMENT: Tuning and Optimisation

Surveys and audits

The first step in reviewing a maintenance regime for optimise is to conduct a survey or audit of the systems concerned. Surveys and audits are periodic assessments that offer the opportunity to establish the status of a building or system in relation to a wide range of performance issues. Surveys are generally limited to listing and checking items and plant whereas audits generally also involve some form of quantitative measurement and data analysis. Audits and surveys form a key component of maintenance management and are essential tools for optimizing sustainable performance.

Types of audits and surveys that can be applied to HVAC&R systems when considering system optimisation include:

Safety survey

energy audit

water audit

maintenance survey

indoor air quality audit

occupant satisfaction survey

Legionella risk management survey

Auditors and surveyors must be competent in the field and have the appropriate accreditation and licenses required to carry out the respective work.

A safety survey would include a survey of the essential safety measures within the building and an assessment of the safety of plant and systems with regard to operator and service technician safety. This ensures that the HVAC&R systems and associated mechanical services meets the AS 1851 Standard or the mandatory regulated state or territory regimes with regard to essential safety system maintenance. The system must function, be tested at the correct intervals and have test documentation in place to prove that the maintenance has been carried out correctly. 

An energy audit examines energy using equipment and operating patterns to provide a breakdown of energy consumption within a site. The audit should identify major energy users, investigate consumption trends, define and monitor key performance indicators which can be compared to industry benchmarks. The audit should examine the energy sources being employed as well as energy end use. The audit should also identify and assess the feasibility of any energy saving opportunities.

A water audit comprises a breakdown of water usage and consumption within a site. The audit should identify major users, investigate consumption trends, define and monitor key performance indicators which can be compared to industry benchmarks. The audit should also identify and assess the feasibility of water conservation measures.

A maintenance survey is carried out to determine the extent of the plant involved and the condition of the plant before any maintenance is started.  In this way it may be determined if there is any repair or replacement work required to bring the equipment up to a standard acceptable to all parties involved and to which it may be maintained. Maintenance surveys also review the access provided, the service provisions for maintenance work, the maintenance documentation, documentation management and maintenance programming.

An indoor air quality audit reviews the air distribution system against the original design, reviews the current floor layout, checks air flows and minimum outdoor ventilation rates and quantitatively assesses the quality of air at various locations at the site. Ducts and air handling plant are reviewed for cleanliness or moisture and a survey of building occupants is often carried out. A report is produced identifying operational or behavioural problems and recommending solutions including changes to maintenance or operational practices.

An occupant satisfaction survey can ask the opinion of building occupants about their satisfaction level with a range of issues relevant to HVAC&R systems including thermal comfort, ventilation and noise. Results are collated, and an action list of operational or behavioural problems and solutions is compiled.

A Legionella risk management survey is generally applied to a cooling water systems or cooling towers by qualified experts in the field to assess the performance and safety of such systems and to help identify and manage the critical risks as outlined in AS/NZS 3666.3.

System optimisation procedures

The objective of system optimization is to address many of the common areas of waste in HVAC&R system operation including:

• Simultaneous heating and cooling
• Oversized plant and equipment
• Overridden variable speed drives
• Overridden economy cycle
• False or repeatedly ignored alarms
• Inefficient piping and ducting layouts
• Poorly located or calibrated sensors
• Poor system integration
• Inappropriate control sequences
• Altered control set points
• Inappropriate lighting and controls
• Envelope air leakage and moisture management
• Afterhours access to air conditioning

System optimisation can be targeted at a range of objectives:

• energy use
• thermal comfort
• IAQ
• Service security

The following is a basic 8-Step process that all system optimisation protocols should follow; Plan – Implement – Measure – Maintain.

It should be noted that systems cannot be optimised unless any obvious underlying design and construction faults are first rectified.

For a detailed description of the processes and methodology for optimising the controls for building HVAC refer to AIRAH/OEH HVAC Optimisation Guide.

System tuning

HVAC&R systems can be highly engineered, incorporating sophisticated design and technologies in a variety of innovative ways. These systems need to be continually tuned to ensure that their operation and performance is optimal. Initial tuning begins at the commissioning stage where the system is set up to meet the design requirements. System tuning is the operation of adjusting the commissioned system to meet the actual needs of the building occupier.

Tracking performance trends against maintenance activities is an essential aspect of tuning the building systems. Tuning is an iterative process and relies on accurate and complete maintenance records for optimum outcomes.

If there is no management plan in place to ensure periodic system tuning, if system monitoring is not in place and if the knowledge loop regarding HVAC&R services between system maintainers and building managers is not facilitated, there is a risk that severe operational inefficiencies may occur, resulting in higher operating costs, poor indoor environment quality, and increased risks for the building owner and occupants.

The most common system deficiencies addressed by system tuning are:

• Incorrect sensor or controls calibration.
• Inappropriate control strategy (non-optimum).
• Incorrect scheduling of HVAC&R plant.
• Simultaneous heating and cooling.
• Underutilized control functions.
• Inadequate metering and sub metering.
• Short cycling of equipment.
• Incorrect building documentation.
• Lack of operator/user training.
• Malfunctioning equipment.

Building and system tuning is an iterative process. Generally, less and less problems are encountered over time when a systematic system tuning program is adopted. Conversely, when building and systems are not periodically tuned increasing levels of operational problems are encountered over time.

Re-commissioning

Where systems have been inadequately commissioned or where systems have not been tuned as an ongoing process then re-commissioning may be required. Generally, most HVAC&R services should be periodically re-commissioned to provide assurance that they are operating as intended. In particular system set points and control settings may need to be reset from unauthorised changes. Depending on the precise requirements of the occupants the initial commissioning may need to be readdressed if the final operation requirements differ significantly from the designed requirements.

Re-commissioning may be required when tenancy changes occur or when tenants undertake fit-outs of tenanted areas. Re-commissioning should be undertaken when a building changes use or after a period of non-occupation or use. Re-commissioning may be instigated in response to audit reports or occupant complaints. Re-commissioning is also a useful tool when addressing long-term operational problems of a system.

Where modifications are undertaken to a part of the HVAC&R system the entire system needs to be recommissioned as do any associated systems. Any re-commissioning work needs to be well documented including updating the system operating and maintenance manuals and as-installed drawings with any changes or modifications.

For a detailed description of the processes and methodology for re-commissioning and retro-commissioning buildings with HVAC refer to AIRAH DA27.

Recalibration

An important step in system tuning and any re-commissioning work is to recalibrate any sensors or controls on a system to ensure their correct accuracy and set point. Temperature sensors, flow sensing devices even time clocks can lose accuracy over time providing incorrect information to the control system and creating inefficiencies and a lack of proper system control. Confirming the correct calibration of these devices and recalibrating where necessary is the first step in any system tuning procedure.

Sensors, controllers and their housings also need to be cleaned periodically to ensure continued correct operation.

Time clock settings should be checked to ensure that they are functional and adjusted correctly to take into account the season, daylight savings and required operating hours.

Controls

HVAC&R controls are initially specified and designed to provide comfort conditions and efficient system performance. The full capability of any automatic controls should be investigated as there may be more complex functionality or programming options that can be utilised to improve system performance. Control systems should be fully utilised and not reduced to the functionality of a time clock.

Maintenance of digital and electronic control equipment requires a special level of expertise to diagnose and solve a problem.  Because of the complexity of this type of system it is common for a building operator to simplify the system to the stage where it can be understood but where it no longer retains the control or efficiency for which it was designed.  If this has happened it is essential that the maintenance contractor re-establishes the original intent or has the system redesigned, by a competent person, to suit the new conditions while not losing any of the plant efficiency in operation and performance.

Carrying out routine checks on time switches and optimiser controls ensures that settings are as intended and appropriate.

Even simple manual and solid-state controllers need to be periodically recommissioned and recalibrated. Re-commissioning a controller ensures that its settings are optimised for the current system operating requirements. Recalibrating a controller ensures that the device is operating accurately and effectively.

Typical checks for controls include:

• Effective functioning of safety devices
• Sensor set point calibration
• Actuator functionality testing

Developing technology tends to provide continuing opportunities for improvement of control systems. Any modifications to controls and system capabilities should be supported by appropriate training and updates to operating and maintenance manuals.

Building management and control systems (BMCS) often incorporate some level of automatic system or self-monitoring facilities. Irrespective of these facilities and the results provided sensors, controllers and actuators should be physically checked and calibrated to ensure that they meet the design intent.

The maintenance of BMCS is generally carried out by the original control equipment manufacturer or a specialist contractor. Maintenance routines should consist of the functional testing of system hardware (sensors, controllers and actuators) and a review and tuning of the software system and protocols being applied.

For a detailed description of the processes and methodology for maintaining and re-commissioning building management and control systems refer to AIRAH DA28.

Cooling and reheat

A common inefficiency found in HVAC&R systems is cooling and heating systems fighting each other or operating at the same time. This can waste considerable energy and put considerable stress on the plant while failing to achieve the internal comfort conditions required.

Systems with cooling and heating capabilities should be investigated to ensure that cooling and heating systems cannot operate simultaneously.

Outdoor air

Outdoor air flow rates and distribution should be checked against the original design intent and actual building populations and usage patterns. Any economy cycle or free cooling cycle capability of the system should be checked, and the settings confirmed. It is not uncommon for outdoor air economy cycles to be provided but to be functioning incorrectly and inefficiently (without the original design intent).

Air flows and balances

Dampers, filters, terminal units or controls may have been adjusted in an adhoc manner. Air flows should be checked and verified against any new partition layouts tenancy changes etc. Building inflows, exhaust quantities and pressurization effects should all be investigated. Air distribution systems should be rebalanced where necessary. Fan operating points on the manufacturer supplied fan curve should be investigated with regard to the efficiency of the fan operation.

Water flows and balances

Valves, strainers or controls may have been adjusted in an adhoc manner. Water flows should be checked and rebalanced where necessary. Pump operating points on the manufacturer supplied performance curve should be investigated with regard to the efficiency of the pump operation.

Energy efficiency maintenance

Effective maintenance strategies and procedures ensure the efficient operation of systems and equipment which contributes to the overall energy efficiency of the building. Certainly, maintenance strategies such as coil cleaning, checking refrigerant charge, component servicing and controls optimisation can be applied to target reducing energy consumption and improving energy efficiency and productivity.

Where the building or systems have inherent faults, failings or inadequacies an energy optimisation process may be applied to HVAC&R.

Energy optimisation and HVAC&R

Building energy use

The energy used by a building is largely influenced by three factors:

1. The building construction (size, glazing, fabric, orientation and location)
2. The building services (efficiency, appropriateness, design)
3. The building management and operation.

The first step in any energy efficiency maintenance program is the establishment of an energy management policy leading to the development of an energy management system.

HVAC&R potential energy wastage

Energy is often wasted by HVAC systems and often this is masked by the system itself whilst it continues to provide adequate comfort to occupants. 

Some of the areas of energy waste typically encountered in unmaintained HVAC&R include:

• Control set points and schedules (internal temperatures, 24/7 plant operation)
• Absence of temperature lock outs
• Simultaneous heating and cooling (Cooling and heating systems working against each other)
• Excessive use of reheat (can mask control and operation problems)
• Dirty or blocked heat exchange surfaces (chillers, boilers, cooling towers, coils)
• Clogged or blocked filters (air and water)
• Incorrect refrigerant charge (chillers and DX)
• Water leaks and excessive water use (cooling tower bleed)
• Bypass in valves and dampers
• Excessive outdoor air ventilation flow rates
• Air leakage in ducts, connections, access panels
• Incorrect economy cycle operation (operating during high/low outdoor temperatures)
• Poor air handling control (VAV pressure control)
• Inappropriate or ineffective mechanical night purge (in high thermal mass buildings)
• Inappropriate pre-heating/pre-cooling schedules (non-optimum start/stop)
• Thermal bridging (duct/pipe insulation, equipment insulation, building fabric)
• Excessive air infiltration (building pressure, facade integrity, zoning)
• Excessive throttling using dampers or valves (particularly on index circuits)
• Inefficient motor use or missed VSD opportunities
• Missed energy recovery opportunities
• Incorrectly calibrated temperature and humidity sensors
• Deferred maintenance (covering many of the above items as well as manufacturer’s instructions)
• Inappropriate access to controls (unlocked thermostats)
• After hours system access (systems running 24/7 instead of on demand)
• Lack of knowledge of BMCS and graphical user interface (diagnostic screens, alarms, trends).

Common causes of HVAC system performance degradation in buildings include:

• Refurbishment of spaces and HVAC system - It is important that the BMCS/controls be updated to reflect any new fit-out or repurposing of spaces.
• Failure of control components - Almost every component of the BMCS system, whether it be a damper actuator, a valve actuator, sensor, controller, etc. has a life expectancy that is shorter than the life cycle of the building itself. Components can also fail prematurely, due to some defect, improper installation or abnormal duty cycle.
• Inadequate preventative maintenance - The best preventative maintenance program is one that is tailored to the specific system, rather than just scheduled quarterly or annually whether needed or not. A good example is the outdoor airflow measuring sensor. As this sensor can collect airborne particles its accuracy is dependent upon how clean air intakes are maintained and how often filters are changed. Sensor accuracy affected by airborne particles, can lead to improper building ventilation and pressurisation issues.
• Control sensor accuracy drift - Critical control sensors, such as humidity sensors and carbon dioxide sensors must be checked for proper calibration. While sensor inaccuracies can be masked by the BMCS, it is a source of inefficiency, e.g.  demand control ventilation with carbon dioxide sensors. It is not unusual to find measurement errors to be out by 200 ppm when specifications may call for no greater than 75 ppm for a period of 5 years after installation. 
• Operator overrides - Overrides or automatic control features can be necessary to address temporary operational conditions or situations, but they are often left in place much longer than intended and can result in inefficient operation.
• Oversizing - During design and construction, safety factors can sometimes be used to account for unknowns that can cause equipment to be oversized and temperature control zone airflows to be greater than needed. While this oversizing can be masked by the BMCS, it is a source of inefficient operation that can be rightsized, even in the installed condition.

Energy management

Maintenance management systems often incorporate the monitoring of energy consumption, not only to reduce energy costs but also to provide plant performance data of a condition monitoring nature and system performance data or an operational nature (efficiency and costs).

Energy costs are a significant part of the operating costs of HVAC&R plant. Improving energy efficiency has the potential to substantially reduce costs and environmental impacts.

Energy management is a continuous process, which may be conveniently set out as three stages: audit, formulate strategy, and carry out improvements to reduce energy.

Stage 1 – Energy audit

The energy audit includes examining and assessing the building and plant efficiencies. This activity usually includes a walk-through audit as a start, followed by an analysis of tariffs to ensure they are appropriate, monitoring of energy consumption over a period and a detailed examination of the energy systems.

AS/NZS 3598.1 provides best practice requirements for energy audits of commercial buildings and related operations. AS/NZS 3598.2 covers industrial and related activities.

Stage 2 – Energy strategy

Based on the audit, a detailed cost benefit study may be carried out to establish priorities for implementation of measures having varying financial payback periods. A number of other benefits are realised when such an approach is adopted in formulating, developing, implementing and updating an energy management plan which is integral with maintenance management:

• commitment by management to the requirements of maintenance
• reduced downtime and optimised maintenance and energy costs,
• improved understanding of the operational relationships between each work group at all levels from management to workforce,
• improved understanding of the role of various plant items,
• preparation of a strategic plan that captures the experience of the workforce,
• a rational basis for providing an affordable level of maintenance with realistic long-term maintenance objectives,
• ownership of the plan at all levels,
• regular reviews and updates,
• Improved compliance with occupational health and safety requirements.

Stage 3 – System modifications

These will depend on the nature of the recommendations arising from the audit and the strategic plan. Note that any modifications to NCC required provisions may need approval from a building official. Typical energy saving measures include:

• optimal stop/start,
• load reset on variation in outdoor air temperature,
• greater use of sub metering,
• air handling system rebalancing,
• recalibration of controls,
• dampers repaired,
• reducing maximum demand,
• heat reclaim,
• reset cooling and heating fluid temperatures.

Energy saving modifications

Energy savings that are achieved by improvement of the plant by modernisation of the installed equipment are often expensive however it is possible to upgrade some items which will achieve savings simply by making use of latest developments in a particular area.  This is most apparent in the areas of controls or of air distribution.  The maintenance contractor should keep abreast of developments in all areas and advise the owner when it is considered that modification can be made to the plant to economic advantage.

In many cases, improvement can be made, without capital investment, by improvement of the operational strategy of the building.

The following list of some possible energy conservation measures has been prepared for consideration during HVAC&R maintenance management.

• Reduction in running times during unoccupied hours.
• Installation of time clocks.
• Installation of more meters and sub meters to better monitor energy use.
• Rate of mechanical outdoor air ventilation based on atmospheric monitoring system
• Reduction of toilet exhaust running hours.
• Reduction of car park mechanical ventilation system running hours.
• Operation of car park ventilation based on atmospheric monitoring system.
• Provide control of mechanical plant room exhaust volumes.
• Provide for compensation of space temperatures dependent upon ambient conditions (i.e. raise room temperatures in summer and lower them in the winter).
• Ensure that all steam leaks are repaired as soon as possible, particularly at steam traps.
• Reduce heat leakage due to infiltration by provision of weather sealing at doors and windows.
• Provide window tinting or shading where appropriate to reduce solar penetration.
• Investigate building/zone pressures to determine the effect on air infiltration/exfiltration.
• Set space temperatures back during periods of non-occupancy and reduce the temperature differential between heating/cooling medium and space temperature to reduce losses from piping.
• Provide economy cycle to take maximum benefit from the ambient conditions.
• Ensure that the thermal insulation of the building and plant is at the most effective level.  Consider the use of double glazing if appropriate (note that double glazing doesn’t necessarily save energy in temperate climates).
• Make use of exhaust/spill air for heat recovery where this is economically feasible.
• Reduce outdoor air quantities to minimum levels to comply with Australian Standards.  Use return air for warm up, in unoccupied areas and for night purge systems.
• Consider the possibility of power factor correction for large motors and other loads.
• Identify plant that may be shut down or managed to reduce peak electrical demand.
• Upgrading plant with more efficient motors and drives.
• Utilise the building automation system to provide automatic reset of the chilled water temperatures.

Any energy conservation measures need to be properly costed including life cycle costs and financial payback periods. Implementation of any of the above energy conservation measures should not be adopted without an appreciation of their full impact on the operation of the building e.g. reducing the temperature differential between heating/cooling media and space temperature may cause loss of control in zones with large substantially constant loads.

Water conservation maintenance

Water management systems

Effective maintenance strategies and procedures ensure the efficient operation of systems and equipment which contributes to the overall water consumption profile of the building. The first step in any water conservation maintenance program is the establishment of a water conservation policy leading to the development of a water management system.

Any water management system should begin with a water audit. A water audit breaks down water consumption, identifying major users and consumption trends. The audit should identify and assess the feasibility of water conservation measures and any maintenance strategies for reducing water use. Any water conservation measures adopted should be fully costed.

Cooling water systems

A major water user in HVAC&R systems is evaporative cooling towers. The following issues have been identified that need to be addressed for effective water management in these systems:

• Metering - Fitting sub meters to cooling tower make-up water supply and bleed off lines is an effective way of focusing on water use efficiency and of identifying operational problems that may occur in the future.
• Leaks – Leaks can occur in basins, casings, pipes, valves, pump seals or flexible connections. The system should be checked regularly for leaks and any leak repaired immediately.
• Overflow – Overflow is an uncontrolled water loss caused by water flowing back into the cold water basin once the circulating pump has stopped. Any evidence of overflow from the tower basin should be noted and the overflow reason investigated. Overflows can be the result of operational problems, inadequate maintenance, incorrect system balance or poor design.
• Make-up – The makeup water control device should be routinely inspected and maintained to ensure correct operation and volume delivery. Any backflow prevention device should be tested and maintained in accordance with AS 2845.3.
• Bleed – To control the suspended solids and total dissolved solids in the cooling water some water is bled off the system and replaced with fresh make-up water. The settings of automatic bleed off systems need to be checked to ensure that the bleed off rate is not too great and that bleed off cannot occur during any dosing of water treatment chemicals. AS/NZS 3666.1 specifies that bleed off should be controlled automatically.
• Sensors - Cleaning and regular recalibration of the automatic system sensors is important to ensure correct operation of the system.
• Drift – Water is carried from the cooling tower in tiny droplets entrained in the exhaust air. Current standards limit cooling tower drift to 0.002% of the system flow rate. Many older towers should have their drift eliminators checked for efficiency and possible upgrade.
• Splash – Water can be accidently lost from a cooling tower due to the splashing action of falling water within the tower and the action of prevailing winds. This is usually due to poor design and the fitting of louvers, splash mats or wind breaks may be required.
• Efficiency – In simple terms, and with all other factors being equal, systems that are operating more efficiently will consume less water that system that have operational inefficiencies.

Water leaks

The best way to check for water leaks is a visual survey of the plant. Water leaks may be intermittent. Water meter and consumption levels should be checked regularly to detect changes in usage patterns. A sharp increase in water use could indicate a leak in the system.

The use of water sub meters in this application is particularly useful. When all water using devices are turned off on a particular circuit the less obvious water leaks will be revealed if the meter continues to tick over.

Water reuse and recycling

There may be opportunities to reuse or recycle waste water from HVAC&R systems. Large evaporative cooling systems can create significant volumes of bleed water which can be reused in some instances. Care should be taken with waste water containing high levels of treatment chemicals.

Where condensate is collected and piped to drain there may be the potential to recover this relatively clean water and re-use in another area rather than discharging it to sewer.

Maintenance practices

Water is often used during maintenance activities for cleaning or simply by draining down equipment during maintenance procedures. Maintenance staff and work instructions should minimise water use where practical.

Water efficiency audit

Water efficiency audits need to be carried out periodically to ensure that the system continues to perform at the required level.

Refer to AIRAH Best Practice Guideline – Water conservation in cooling towers for further detailed information. www.airah.org.au

Refrigeration system maintenance – AS/NZS 5149.4

AS/NZS 5149.4 specifies the environmental and safety requirements for the maintenance and repair of refrigerating systems. The maintenance requirements of AS/NZS 5149.4 do not apply to air conditioning and refrigeration appliances that conform to AS/NZS 60335.2.40. These appliances should come with their own operating and maintenance instructions.

To claim compliance with AS 5149.4 refrigeration system maintenance would need competent maintenance personnel to apply and document the specified maintenance procedures, including regular leak inspections, in accordance with the system operating and maintenance instructions and all national regulations.

AS/NZS 5149.4 competence

AS/NZS 5149.4 states that the personnel charged with the operation, supervision and maintenance of the refrigerating system must be adequately instructed and competent with respect to their tasks. A competent person is required for all the following tasks:

• All maintenance service and testing
• Leak detection and repair
• Equipment replacement or changes
• Refrigerant recovery, reuse, recycle, reclaim and disposal
• Draining oil from systems
• Welding and brazing

Other trades working on the system (e.g. electricians or controls technicians) must be supervised by a competent person.

The standard requires competent maintenance personnel to know:

• the in-service inspection requirements
• the day-by-day functioning, operation and monitoring of the systems
• the change of refrigerant type process (outlined in AS/NZS 5149.4)
• the properties and handling rules for the refrigerant in use
• the safety measures to be observed.

Maintenance requirements

Each system must have an operation logbook and be the subject of preventative maintenance procedures specified in the system operating instructions that must be provided under AS/NZS 5149.3.

For a refrigerating system to comply with AS/NZS 5149.4 it must have an updated logbook (AS/NZS 5149.4 Clause 4.3) to record:

• details of all maintenance and repair work
• quantities, sources and kind (new, reused or recycled) of refrigerants charged in to, or transferred out of, the system
• changes to or replacements of, components or parts of the system.

The person responsible for placing the system in operation must ensure that operating personnel are instructed in the correct system operation, including the safety aspects and the requirements around handling refrigerants.

Maintenance procedures

The installer is responsible for highlighting the need for operator instruction, this includes how to maintain the system and the associated safety requirements.

A minimum in-service inspection regime is provided in Annex D of AS/NZS 5149.4 to assist users where no national regulations apply.

Instruction manual

Under the installation rules of AS/NZS 5149.2 and AS/NZS 5149.3 the installer must supply a system instruction manual. This must include the maintenance instructions for the entire system with a time schedule for preventative maintenance with respect to (refrigerant) leakage.

The instruction manual must include the purpose, description, schematics of the system, operating instructions, fault detection and diagnosis, precautions, protective measures and appropriate warnings and first aid.

Refrigerant leak testing

Preventative maintenance must be applied as outlined in the system instruction manual (see AS/NZS 5149.2) and include regular leak testing inspections and checking of the safety equipment. Procedures include applying a leak inspection regime, using direct and indirect leak detection methods every three, six or twelve months, depending on the mass of refrigerant contained in the system (the refrigerant charge).

• Inspections every month for systems containing 300 kg or more refrigerant, every 6 months for systems containing between 300 kg and 30 kg and every 12 months for systems containing between 30 kg and 3 kg
• Systems with over 3 kg of refrigerant should have a refrigerant logbook to record the quantity of refrigerant installed, added, or recovered.
• When a system contains more than 300 kg a refrigerant detection an alarm system is also required, and these must also be maintained annually.

Action must be taken to eliminate every leak that is detected. Leak sites should be re-inspected one month after repair.

Refrigerant management

Refrigerant leak detection

Refrigerant leaks and their containment is a serious issue for safety, environmental and operational reasons. Refrigerant leak detection should be incorporated onto the refrigeration system and within the plant room or any confined space where concentrations due to a leak could become dangerous. The safety requirements for the design of refrigerating systems are covered in AS/NZS 5149. Refrigerant leak detection systems can be retrofitted and can be linked to building management and control systems.

Automatic refrigerant pump down

In order to minimise the release of refrigerant to the environment automatic leak detection systems should be complimented with automatic refrigerant pump down systems. These systems may be retrofitted. Manufacturers’ advice should be sought.

Refrigerant handling

All applicable refrigerants and refrigerating systems must be handled in accordance with the Australia and New Zealand Refrigerant Handling Code of Practice.

Hydrocarbon refrigerants, CO₂, ammonia and other non-fluorocarbon refrigerants should all be handled in accordance with AS/NZS 5149.4 and the appropriate industry guidelines.

Refrigerant replacement

Consideration may be given to replacing an existing older refrigerant with a more efficient or less environmentally damaging modern replacement. Manufacturers’ advice should be sought. AS/NZS 5149.4 provides a refrigerant replacement procedure.

The standard steps users through the required procedures for changing the refrigerant type in existing systems. This includes the steps to take when planning a refrigerant conversion including verifying that all materials, components and oils are compatible with the new refrigerant, and checking that the component allowable pressure (PS) cannot be exceeded, the relief valve size, motor current ratings and receiver size is adequate for the new refrigerant type and charge. A 14-step procedure for implementing a refrigerant type change is also included.

Specific conversion procedures are required when a change in refrigerant classification is involved.

Indoor air quality maintenance

Maintenance practices contribute significantly to the quality of indoor air. The first step in any indoor air quality maintenance program is the establishment of an indoor air quality policy leading to the development of an indoor air quality management system.

Any indoor air quality management system should begin with an indoor air quality audit. Issues which should be assessed in any air quality audit or review include:

• Outdoor air ventilation rates
• Application and maintenance of air cleaning devices
• Air handling unit and duct cleanliness
• Air distribution and balancing
• Air analysis and assessment
• Recirculation rate, air change rate
• VAV terminal unit settings and operation.

AIRAH application manual DA26 provides comprehensive information on indoor air quality.

Performance based microbial control

Cooling water systems – AS/NZS 3666.3

The AS/NZS 3666.3 standard provides a performance-based approach to the maintenance and verification of microbial control within cooling water systems, specifically those systems that incorporate a cooling tower.

The approach outlined in the standard is prescriptive and combines a risk assessment and management process for a range of specified risk factors with a performance monitoring and control regime which includes prescriptive control strategies when key performance indicators fall outside of the specified performance limits. Key performance indicators are defined as risk factors that are testable, assessable and controllable for the performance, monitoring and verification of microbial control within the system.

For an AS/NZS 3666.3 approach the following steps must be implemented:

Step 1 - A risk assessment of the cooling water system and its surrounds is undertaken by a competent person. All of the risk factors outlined in Table 2.1 of the standard are required to be assessed and controlled. The reasonably practicable test applies to the control of risk. The objective of the risk assessment is to provide appropriate control strategies that will reduce the inherent (or initial) risk level posed by the system to a low residual (or remaining) risk level. See AS/NZS 3666.3 Section 2.

Step 2 - The risk assessment and control strategies are documented in a risk management plan. Control strategies must include water treatment and an inspection and maintenance regime tailored to the risks identified for the system. Each site and installation is assessed individually using the standardised risk assessment methodology. The risk assessor can use quantitative data, qualitative data and expert judgement to assess the consequence and likelihood of any inherent risk, and develop control strategies that will reduce the residual risk to an acceptable low-risk level. See AS/NZS 3666.3 Section 2.

Step 3 - The risk management plan is implemented including the inspection and maintenance regime developed for the system and its components, as documented in the plan. All risk factors identified by AS/NZS 3666.3 as key performance indicators are monitored and controlled. Monitoring is typically performed monthly to align with typical inspection and service schedules. See AS/NZS 3666.3 Section 3.

Step 4 - The control strategies outlined in the standard for the presence of microbial growth (Legionella or HCC), water quality and temperature management, are implemented and the results and corresponding actions recorded. See AS/NZS 3666.3 Section 3.

Step 5 – The results of all monthly monitoring and control activities are documented and retained. Risk assessments are reviewed when changes to the system or surroundings occur or at least every five years.

Note that in some jurisdictions in Australia this process is required to be audited to provide independent verification of compliance. Refer to the Public Health and/or WHS regulations that apply in your jurisdiction.

Air handling systems – AS/NZS 3666.4

The AS/NZS 3666.4 standard provides a performance-based approach to the maintenance and verification of microbial control within the air handling systems (ducts and components) of buildings.

The standard is offered as an alternative to the AS/NZS 3666.2 prescriptive maintenance procedures.

Similar to the AS/NZS 3666.3 approach the standard requires that a risk assessment of the air handling system and its surrounds is undertaken by a competent person. All of the risk factors outlined in Table 2.1 of the standard are required to be assessed, and control mechanisms nominated as appropriate to reduce risks to a ‘Low’ risk level. A compliance schedule of all actions in relation to the risk assessment must be prepared.

Verification by a competent person that the compliance schedule for the air handling has been implemented is required every 12 months. Where verification is not proven then the system condition must be reassessed, and the appropriate corrective action implemented.

Incorrectly sized plant

Oversized plant

Many existing systems incorporate oversized plant which can result in excessive energy consumption, increased wear and maintenance and reduced service life.

Plant can be oversized for a number of reasons including:

• Specified design requirements being greater that actual operational requirements.
• Margins added during design calculations to account for unknowns or uncertainties.
• Allowances in-built into published design data and calculation methodologies.
• Installed plant with larger standard capacities than operational or design requirements.
• Changes that occur after system design/installation (glazing, shading etc).

Oversized plant cannot always be readily identified. The following system characteristics may indicate oversized plant:

• Modular plant with modules that are never called on to operate.
• Internal conditions maintained even in extreme outdoor ambient temperatures.
• Short internal space warm up or cool down times.
• Air or water temperature differentials that never reach the design parameters
• Drive motor running currents well below the full load current.
• Automatic control valves on heating or cooling coils never fully opening.
• Unstable systems prone to hunting or frequent switching often contain oversized plant.
• Results of air analysis consistently showing signs of over ventilation (low CO₂ levels).

System performance monitoring and benchmarking is essential to confirm plant over sizing and extensive performance testing by a commissioning expert under varying conditions may be required to determine the extent of the problem.

Where over sizing has been confirmed, actions can be taken to improve plant efficiency and reduce energy consumption. Possible remedial actions include:

• Take unused plant modules offline for backup or duty/standby.
• Reduce volume flow rates in air and fluid distribution systems.
• Reduce drive speeds.
• Install reduced size control valves or dampers.
• Reduce outdoor air quantities to match operational requirements and standards.
• Check control regimes to ensure that plant operating times are reduced to a minimum.

Any corrective actions with regard to oversized plant need to be properly costed including life cycle costs and financial payback periods (see Appendix E). Implementation of any of the above remedial actions should not be adopted without an appreciation of their full impact on the operation of the system or building. Corrective actions may need to be finetuned to achieve the final optimum setting.

Undersized plant

Undersized plant is easier to identify within a system however the maintenance and failure implications are significant and undersized plant may require additional maintenance actions and more frequent maintenance than that normally recommended.

Actions can be taken to improve system performance including;

• Reducing loads on the system.
• Improving system component efficiencies.
• Upgrading plant.

In many cases and where operational performance cannot be achieved, undersized plant should be replaced or enhanced.

Refurbishments, replacements and upgrades

Scheduled refurbishments, replacements and upgrades provide an opportunity to improve the performance and sustainability of older HVAC&R systems. When replacing existing equipment current and future requirements should be evaluated. Actual capacity requirements for plant can be measured rather than calculated providing good opportunities for right sizing of plant.

Energy efficient alternatives can be adopted, and improved control or operating regimes applied. Similarly water efficient alternatives or design strategies can be adopted to improve overall system sustainability outcomes.

Commissioning procedures should ensure that any new plant or protocols does not adversely affect the performance of existing systems and re-commissioning of existing systems may be required.

Detailed information on commissioning, re-commissioning and retro-commissioning buildings is provided in AIRAH DA27.

Appendix A - HVAC&R maintenance schedules

This Appendix is available as a separate document DA19 Appendix A HVAC&R maintenance schedules

Appendix B - Preventative maintenance schedule example

This Appendix is deliberately left blank

Appendix C - Operating and maintenance manuals

C1       Benefits

Operating and maintenance (O&M) manuals are documents containing comprehensive information and instruction on the correct use, operation and maintenance of the plant.

The intent behind these manuals is to:

• enable correct operating and maintenance procedures to be followed
• provide a basis for the planning and control of maintenance and operational activities
• provide a framework for the collection of data able to be used for performance evaluation during the life of the plant

Following O&M manual instructions should achieve optimum performance, operational life, safety, reliability and sustainability of plant as well as effective use of maintenance staff and contractors.

The provision of operating and maintenance manuals is a mandatory requirement of AS/NZS 3666.1, with the content specified in AS/NZS 3666.2.

C2       Uses

Maintenance provider

Where maintenance is carried out under contract the O&M manual serves as an invaluable instruction book for maintenance contractors during the life of the plant.

The manual is also important to the system owner and the installation contractor.

Plant owner

For the plant owner (or manager), the O&M manual can serve as a readily accessible and comprehensive reference source throughout the life of the plant for the purposes of:

• training and supervising staff in the correct and efficient operation and maintenance of the plant and avoidance of breakdown due to misuse or neglect
• carrying out scheduled equipment re-conditioning or rectifying accidental breakdown in the minimum time
• securing quotations for preventative maintenance or service contracts and for supervising such work
• planning later additions or modifications to the plant.

Installation contractor

To the plant installation contractor, the O&M manual is invaluable:

• as a reference for operating the plant during the commissioning period and for subsequent service
• as a means of avoiding needless service calls and queries in the contract maintenance period
• as a basis for quoting for a preventative maintenance or service contract and for supervising the performance of this work
• as a reference source for the identification of spare parts and replacements
• as background information for quoting any later additions or amendments
• as a continuing advertisement to both the present and any future clients, consulting engineers and other parties who may be exposed to it
• preparation of the manual may often reveal design or installation errors in time to allow correction before inconvenience or damage results.

C3       Format

The format of O&M manuals should be by agreement between the system owner, operator, designer and installer. Increasingly all building documentation is being provided in electronic format.

O&M manuals presented in electronic format replace hard copy manuals. Digitisation helps users overcome the problem of searching and handling large amounts of system information. Computer based O&M systems may need to incorporate CAD/BIM as-installed drawings/Models, word processed maintenance schedules and operating instructions, commission data spreadsheets, energy management and building management graphics and reporting programs.

There is the opportunity to provide O&M manuals in an interactive searchable electronic format with links back to equipment suppliers and designers websites to assist in keeping the material up to date and importantly to provide access to larger repositories of information relating to best practice system maintenance and operation.

Computer based information systems should offer the facility to print out all or sections of the O&M manual in hard copy format.

An advantage to the end user will be the ease of transferring the documentation into a building maintenance management system.

C4       Contents

As a general guide, the O&M manual should cover the following aspects. The level of detail required will depend on the size and complexity of the plant.

• A statement of the scope and contents of the manual, with index if needed, so that the user may quickly ascertain the extent of its coverage and the location of the information desired.
• A contents and amendments page so that the most up to date version of the manual can be easily identified and used.
• An overall description of the plant, its design concepts and inter-relation with the building or other plant.
• A detailed description of the plant and its function, generally on a system-by-system basis, such that the reader can clearly understand the workings of each section of the installation, and including details of the sequence of operation, control settings, any performance guarantees, and safety controls.
• Full and specific instructions on the operation of the plant, beyond the information usually contained in the component manufacturers' publications, included elsewhere in the O&M manual. In particular it will invariably be necessary for specific instructions to be specially written covering the operation of the specific plant as an integrated system.
• Such instructions should cover normal and seasonal start-up and shut-down, emergency procedure, diagnosis and correction of operating faults, warnings with regard to incorrect operating procedures and, in the case of modular plant, advice on the addition and shedding of plant modules and guidance as to the most efficient combinations of equipment for particular circumstances.
• Full instructions for routine maintenance, again beyond the treatment in the equipment manufacturers' publications. The preparation of an integrated maintenance program and part replacement schedule for the plant as a whole will require special attention.
• Instructions should include details of lubricants, protective treatments, and additives, and warnings regarding incorrect procedures which may damage the equipment.
• System tuning procedures and system troubleshooting charts. Instructions should include the use of tools and test equipment.
• Schedules listing the suppliers and/or manufacturers of components, to assist in obtaining replacements.
• Comprehensive equipment data schedules summarising information which might be required for adjustment, maintenance, repair or replacement of equipment installed.
• A comprehensive set of manufacturers' literature covering technical details and installation, adjustment, maintenance and repair information on the equipment installed. Such literature should be enumerated on a separate listing for ease of reference and as a guide for later replacement of missing or damaged copies.
• Where multiple models or options are covered in the manufacturers’ literature each product data sheet should be marked to clearly identify products and components actually used in the installation.
• A set of "as-installed drawings" drawings such that, in conjunction with the written plant description, manufacturers' literature and other information included, a complete detailing of the plant as installed is provided. These drawings should also be separately listed.
• All relevant test results and commissioning data including schedules of fixed and variable equipment settings.  The O&M manual symbolises the transfer of knowledge about the plant from the designers and installation contractors to the owner and operator/maintainer.
• Provision for recording details of any amendments or additions to the plant, together with resulting alterations to operating or maintenance procedures.
• Copies of manufacturer warranties.
• Copies of all relevant approvals, authorisations, certificates and registrations for plant.

The majority of traditional maintenance instructions are of a visual checking nature. It is therefore important to be specific with instructions in the O&M manual. Simply stating "check safety controls" is incomplete without stating the safety requirements, or "check pressures" is meaningless without stating the expected readings and what must be done if the pressures are unsatisfactory.

C5       Updating

O&M manuals should be periodically updated to:

• Include details of all modifications to plant and systems.
• Take account of developments in technology and knowledge.
• Take account of knowledge gained through operational experience.

Appendix D - Risk based maintenance

D1       Risk

Risk in maintenance management is the prioritisation of events impeding the achievement of organisational objectives. It allows maintenance resources to be focussed on those activities that will avoid the greatest consequence should a HVAC&R system fail.

Risk assessment may be expressed as: Assessing the Consequences x likelihood of a risk.

For example, the consequences of a zone temperature sensor failing in an office building could be compromised comfort in that zone for as long as it takes to identify and replace the sensor.   The consequences of a temperature sensor failure in an operating theatre could impact on life safety.  These events may have the same likelihood, but the contrasting consequences may demand different maintenance activities.

D2       Maintenance risks

Risks derived from maintenance (or lack of it) include risk of injury to occupants of the premises or to maintenance staff or the public.

Financial risk also involves extending the life of the plant and assets as well as other cost-related activities such as level of maintenance, unavailability of parts or products (e.g. refrigerant supplies), supply delays (overseas supplies) or planning and scheduling conflicts.

If plant is not maintained correctly, serviced properly or supplied with suitable replacement parts, then the owner is exposed to the risk of premature plant failure and the need for replacement.

An abundance of health and safety legislation and standards is now in place to ensure that all activities associated with mechanical plant can be carried out safely, i.e. at acceptable risk. Central to the application of risk assessment principles is the Standard AS/NZS 31000 on risk management.

Risk management is the overall culture, processes and structures that are directed towards the effective management of potential opportunities, adverse effects and hazards.

D3       Risk Assessment

Risk assessment is part of risk management and comprises steps such as analysis and evaluation.

Risk assessment is therefore the systematic process of determining what is required to properly control risk to persons, property and environment.

Regardless of the type of risk to be managed, the methodology consists of the same fundamental steps:

Step 1            Establish the context

Step 2            Identification of the hazard

Possibly by audit.

Step 3            Analysis of the hazard

What are the characteristics of the hazard?

What are the risk factors?

Step 4            Evaluation of the hazard

What is the overall level of risk of exposure to the hazard?

Is the risk acceptable?

Can it be readily controlled?

Step 5            Controlling, monitoring and remedial actions

What can be done to avoid or reduce risk?

What can be done to ensure that the acceptable level of risk does not worsen?

What are the key performance indicators (KPI) and their target values?

How are the KPI factors monitored?

What is to be done if a KPI factor moves out of limits?

The main advantages of the risk assessment are:

• The consistent, auditable recording of the reasons for decisions on risk should help in the long-term development of more effective decisions on risk.
• The monitoring of the critical risk factors should activate predetermined contingency plans as soon as any of these factors move out of range.

There are many applications for risk management per AS/NZS 31000. These include:

• operating and maintenance systems,
• asset management and resource planning,
• business interruption,
• environmental issues,
• occupational health and safety,
• project management,
• legislative compliance,
• Obsolescence.

These applications illustrate the integral nature of maintenance risk management to the effective and efficient operation of any organisation, public or private.

As an example, an organisation may own sites at which may be located potential Legionnaires' disease hazards. A risk management plan for this hazard (which if realised as cases of human disease could be catastrophic for the business of the organisation) can be readily drafted and implemented following the principles set out in AS/NZS 31000 together with AS/NZS 3666.3. This latter standard provides a list of the technical risk factors that need to be evaluated, controlled and monitored. All steps are documented (either software or hard copy) to ensure nothing is lacking in the effective control of bacteria and that the risk of workers at site contracting Legionnaires' disease is reduced to a negligible level.

D4       Rating and managing risk

Steps in the risk rating process

The following is a 10-Steps risk assessment process:

• Identify the system or activity to be assessed.
• Identify the key risks for (and from) the system or activity.
• For each risk identified, list the main sources of the risk.
• Identify the possible adverse impacts arising from the risk.
• Identify what the “Initial” risk rating would be for each key risk, under existing control strategies or if the risk remains untreated.
• To determine the initial risk rating, assess the consequence and likelihood of all risks identified, in light of the scale and sensitivity of the system or activity and any existing controls.
• Detail the additional actions required to manage and reduce these initial risks – these are the risk mitigation or control strategies that are applied to remove or reduce the risk.
• Risks should be assigned a risk owner, who will be responsible for management of the relevant risk.
• Identify what the “Residual” risk rating is for each key risk, once the mitigation or control strategy is in place/applied.
• To determine the residual risk rating, the consequence and likelihood of the risks, after the actions taken to manage and reduce the initial risks have been applied, must be identified and assessed.

Allocating a risk rating

Both initial and residual risks are rated according to an assessment of their potential consequences and the likelihood of their occurrence.

Each risk is assessed for its potential consequences. Potential Risk Categories are:

• Insignificant
• Minor
• Moderate
• Major
• Severe

The consequence terms are self-explanatory, but some judgement is required, and the assessment needs to be considered in the context of a range of potential impacts including; Health and safety (public health and WHS), regulatory, financial, environmental, corporate, legal.

The likelihood of the risk occurring and eventuating into a hazard must also be assessed. Potential Likelihood Categories, and their explanation, are listed in Table D1. Again, judgement is required.

Table D1 Likelihood Categories

The assessments of the consequence and likelihood of a risk are then combined, and a risk rating allocated.

This process is applied to determine a risk rating for each of the risks listed, for both before (initial risk) and after proposed risk treatment strategies are applied (residual risk).

The following Risk Rating Table D2 shows four risk ratings.

Table D2 Risk Rating Table – Four risk ratings Low-Medium-High-Extreme

For simple risks this can be reduced in terms of consequences and likelihood categories, and hence risk ratings, to three or two risk ratings (low/high).

D5       Results of a risk assessment

It is essential that the owner of the asset ensures that:

• The results and findings of the risk assessment properly identify - hazards, risk to various persons, the suitability of existing controls and the need for improved control.
• The results of the risk assessment, rating and proposed risk control processes and activities are appropriately documented.
• The results are reviewed, and recommendations resolved in a timely manner.
• The action to be taken and time for completion are determined and appropriately documented.
• The results and required actions are communicated to all relevant personnel.

Figure D1 Documenting a risk assessment

D6       Ongoing Compliance Audits

Actions determined from the risk assessment must then be implemented, effectively supervised and audited. The audit is usually part of a due diligence program and is sometimes described as a compliance audit. The owner should ensure that:

• Audits are made periodically (frequency dependent upon the application) to ensure risk control methods developed are adequate and are being applied.
• Such audits are made on a sample basis including the most hazardous areas by at least one person knowledgeable in the equipment operation and process.
• Persons affected are made aware of the audit and results.
• The audit findings are promptly reviewed, recommendations resolved, and deficiencies corrected.
• Audit findings and corrections made are appropriately documented.

D7       Specific applications

Guidance on the application of the risk assessment approach to pressure vessels (a special case due to safety implications) is provided in the Australian Standard AS 3873 on the operation and maintenance of pressure equipment. This document provides much detail on the following aspects:

• personnel training,
• operating and maintenance procedures,
• safety management,
• shutdown procedures for boilers,
• maintenance and safe operation of piping systems,
• starting up a boiler after a major overhaul,
• boiler water quality,
• emergency procedures for a low water condition in a boiler,
• modes of failure of boilers,
• application of risk assessment for pressure vessels,
• record keeping.

Guidance on the application of a risk assessment approach to maintenance is provided in AS/NZS 3666.3 for cooling water systems and AS/NZS 3666.4 for air handling systems.

D8       Reviews to operation and maintenance

Owners and their risk managers should:

• Ensure that proper records are kept.
• Update building plans to reflect alterations to plant.
• Maintain a plant inventory and operating and maintenance manuals.
• Keep up to date with changes to legislation that may affect the plant being operated and maintained.
• Carry out any training programs necessary (e.g. as a result of plant replacement).
• Ensure the plant is operating efficiently.

Appendix E - Maintenance costs and reliability

E1       Life Cycle Costing

Life cycle costing for a facility is a systematic methodology for assessing all the significant costs of ownerships over a selected period expressed in equivalent monetary terms. It recognises that the various operational elements within a building system are inter-related over time. That is, a decision made today regarding building services characteristics will not only affect present functioning but will have an impact over the useful life of the facility.

Apart from capital costs, which are not covered in this application manual, the ongoing life cycle costs are formally titled "Cost-in-use" and comprise:

• operating costs
• maintenance costs
• cleaning costs
• alterations and replacement costs

These costs often far exceed the initial capital cost when taken over the useful life of a facility and may have other long term impacts on productivity cost (noise, air quality, thermal comfort) than may be immediately apparent. There is an obvious incentive towards the concept of life cycle costing for an owner-occupier whose interests are best served by ensuring economics for the life of the plant as compared with a developer with motivation towards selling or leasing. AS/NZS 4536 provides an application guide to life cycle costing.

A feature of the life cycle costing methodology is that the cash flow over time for the plant is converted to a common time basis for rational comparison using financial discounting techniques. Hence valid comparisons can be made between alternatives with differing patterns of expenditure and income based on the principle that it is preferable to have $100 today rather than any amount less than $110 in one year's time, assuming, for simplicity, an interest rate of around 10% and neglecting effects of inflation and taxation.

In a life cycle costing analysis, inflation is taken as referring to the rate of price increase of all commodities generally with an associated decrease in purchasing power. Cost escalation is the term used to describe the rise in cost of a particular commodity (sector) and is expressed in real terms, i.e. over and above the general inflation rate. Sectoral inflation includes the general inflation rate. Occasionally some commodities actually become cheaper in real terms, e.g. computing equipment. Such cases are treated by using a negative escalation rate.

Costs are usually estimated in terms of their present day values. Inclusion of future costs at their projected inflated values may complicate the analysis. (If inflated values are used, an inflated discount rate must also be used and the results effectively are the same).

A key element of the methodology is the discount rate chosen. Discount rate is an expression of the time value of money used in equivalence calculations to compare alternatives. It is a value judgment based on a compromise between present consumption of the enterprise and capital formation by the enterprise available for future consumption. Discount rate is not the same as interest rate although, for convenience, a particular interest rate is often judged as appropriate for calculation purposes. Generally, it is the opportunity cost of the funds that is taken as the discount rate.

Discounting is a technique used for converting the value of future cash flows to present values. The notion comes from the fact that a dollar today is worth more than the same dollar sometime in the future. The basic building block for discounting calculation is the equation E1:

                                                   equation E1

where  PW_n      =          present worth of the cost occurring at the year n

            W_n       =          worth or value of the cost (occurring at year n) in real terms

            r           =          discount rate (usually, opportunity cost of the funds)

            n          =          the period in the future during which the cost is forecast to occur.

Opportunity cost is the term used to describe the value to the investor of the capital when put to its best alternative use.

Other terms used in life cycle analysis are:

Amortisation period is the period over which the initial capital cost is written off, i.e. the economic life after which it is more economical to replace the commodity rather than to continue to maintain it. A table of economic lives of equipment, for use as a guide only, is given in Table 2.1.

Sectoral inflation is the total increase in prices within a particular sector or for a particular commodity.

For example, if an item of equipment was priced at $1.00 one year ago and today is priced at $1.30 when the general inflation rate is 10% then the 30 cents (30%) increase is sectoral inflation of which 10 cents is due to general inflation and 20 cents to escalation.

Now                                                                 equation E2

Where     =   escalation rate

                s  =   sectoral inflation rate

                i   =   general inflation rate

Therefore, in the example, escalation rate,

                = 0.182

                = 18.2%

Internal rate of return is that discount rate at which benefits and costs occurring at different times are equated.

Sensitivity analysis is a mathematical appraisal of the sensitivity of the outcome of the evaluation with changes to the estimated parameters involved in the original calculation. It is a useful tool where there is significant uncertainty involved for some components (e.g. energy cost trends). The analysis involves repeating the calculations using the likely limits of the uncertain values.

E2       Financial Analysis

Two straightforward approaches to life cycle costing are known as the Present Worth method and the Total Annual Charges method. Each is mathematically equivalent: the one being the inverse of the other. Other techniques are variations of the Present Worth method and are described under titles such as the Discounted Cash Flow method or the Rate of Return method. Discounted Cash Flow suits a phased investment project as the charges for each year are tabulated and reduced to a present-day value by the appropriate discount factor for that year, then summed over the total period of the study. The Rate of Return method addresses the question "Is it worthwhile (in terms of % annual rate of return) to make an investment now to save on owning and operating costs each year for the study period?"

Relevant formulae for financial assessments are given in the AIRAH Handbook.

Present Worth

Question:         Consider the need to upgrade an air conditioning plant by spending $10,000 with a likely economic life of 20 years for the plant. The annual running and maintenance costs are estimated to be $1500. A discount rate of 10% is assumed. What is the present worth of all this expenditure?

Answer:           The AIRAH Handbook formula for present worth of a series of uniform annual amounts (annuity) to be spent over n years at an interest rate of i, is.

PW        =   {(l + i)ⁿ –1} / i (l + i)ⁿ                                             equation E3

              =   {(1.1)²⁰ – 1} / 0.1 (1.1)²⁰

              =   5.73 / 0.673

              =   8.51

Therefore, Present Worth of capital cost

              = $10,000

Present Worth of running and maintenance cost:

              = 8.51 x 1500

              = $12,765

Total Present Worth

              = $22,765

Total Annual Charges

The AIRAH Handbook formula is

TAC       =   {i (l + i)ⁿ} / {(l + i)ⁿ – 1}                              equation E4

              =   0.1 (1.1)²⁰ / (1.1)²⁰ – 1

              =   .673 / 5.73

              =   0.117 (or )

Therefore, the equivalent annual charge of the capital cost

              =   $10,000 x

              =   $1,175

Annual running and maintenance cost

              =   $1,500

Total Annual charges

              =   $2,675

Note that the Present Worth of this annual charge is $2,675 x 8.51 = $22,765 which is the amount calculated by the Present Worth method.

For further information on these methods including more involved scenarios (such as varying energy rates) refer the Australian Standard AS/NZS 4536. Various spreadsheet software programs are also available to improve speed and accuracy for more complex calculations.

E3       Reliability

Many demand organisations prefer to keep capital expenditure in any one year as low as possible: A small amount spent each year in repairing plant is preferred to a large expenditure in one year only for equipment that will almost invariably have a life of many financial years.

Use of the life cycle costing techniques described above may be persuasive in convincing management that there are economic benefits in expenditure this year in order to affect future savings.

The projected future cost of old equipment entails repair costs, which are very difficult to predict. Some information on repair history is useful in this regard. Of equal importance to both the designer and the maintenance engineer is an understanding of the concepts of Reliability and Availability for the plant. Apart from routine preventative maintenance the satisfactory operation of a system (such as a heating system, chiller system, condenser water system, or overall air conditioning system) can be improved by improving the reliability of that system. Guidance on reliability and maintainability program management is provided in AS 3960.

Reliability is the mathematical probability that a component or a system will not fail at all over a given period of time. For a system comprising a single equipment component, Reliability R = 1 – p, were p is the probability of failure.  The Reliability R is sometimes called the Reliability Factor.

Systems, however, invariably comprise a number of components in series with reduced reliability, as all components must work satisfactorily for the system as a whole to operate satisfactorily.

For the system having three components in series (Figure E1) the Reliability is expressed as:

R = (1 – p₁)(1 – p₂)(1 – p₃)                              equation E5

Figure E1 Reliability of Three Equipment Components in Series

Figure E2 Reliability of Two Equipment Components in Parallel

Table E1 Reliability factors

(to meet full load) for multiple units in parallel based on 90% reliability per unit (i.e. p= 0.1)

Table E2 Reliability factors

(to meet full load) for multiple units in parallel based on 95% reliability per unit (i.e. p=0.05)

Reliability of a system can be improved by adding components in parallel. This is called redundancy. Reliability of the typical parallel – redundant system (e.g. pumps in parallel) is shown in Figure E1 and E2 and expressed mathematically as:

R = 1 – (p₁)(p₂)                                                                        equation E6

Only one of these components (in the parallel system) needs to operate for the system operation to be successful

When the system has units in parallel with all m units on line simultaneously but only j units are needed to meet full load, the formula for reliability is more complex:

                             equation E7

For example, if there are 3 units in parallel and only 2 are needed to satisfy full load equation, E7 reduces to:

R = 3p² – 2p³                                                               equation E8

The relationship between reliability and system complexity can be expressed mathematically. A typical air conditioning system having a mixture of components in series while others are in parallel is expressed as:

R₂ = R₁ R₂ R₃ . . . . . R_n                                                                              equation E9

This means that the more complex the systems, the lower the reliability as the reliability factors for the individual parts are always less than 100%.

Generally, exact probabilities of failure are not known (although availability data may be readily available – see E4) but this may be of little consequence as reliability calculations which compare the risk of failure of alternative arrangements can still be carried out. Typically, the assumed reliability factor is 90% per equipment item. Tables E-3A and E-3B illustrate the use of this technique for assessing the reliability of major equipment items such as chillers having reliability factors of 90% (Table E1) or 95% (Table E2).

In commercial applications the cost of redundant plant must also be considered in relation to improved reliability. For example, if 100% standby is provided for a single unit with each having reliability of 90% as shown in Table E1 the system reliability is 99%.  If however, three units of 50% capacity are installed (m=3, j=2) then although the reliability is marginally less (97.2%) there could be considerable cost savings.

Similarly, if three units, each having a reliability of 90%, are required for full load (m=3, j=3) then the reliability is 72.9%. Adding a fourth unit increases the reliability significantly to 94.8%.  Adding a fifth unit, however, only increases the reliability by a further 4.3% to 99.1%

Chillers however do not usually operate all year at full load. Under partial load conditions system reliabilities increase substantially as redundant capacity emerges. For example, Table E1 shows that 3 chillers installed where 2 are needed to meet full load represents an installed reliability factor of 97.2%. But as load falls such that only one machine is needed, the reliability factor improves to 99.9% (1 chiller needed, 3 installed). The figures are even better with the 95% reliability factor for a single unit as shown in Table E2, but the principles are the same.

Some examples of reliability with other combinations are shown in Table E3 and Figure E3. In the left hand column of Figure E3 one unit satisfies the load. In the right hand column two units in series are required to meet the load. In the last example in Figure E3, a system is shown with two components in series (end to end chain), two levels of redundancy and the ability to cross connect. The probability of success for this system is 98.4% even assuming the low reliability figure of 80% for each unit.

Table E3 Reliability applications with 80% reliability (p = 0.8) for each unit

Figure E3 Reliability applications with 80% reliability

E4       Availability

High reliability is of little practical use if the equipment selected requires a long time for repairs to be carried out. The concept of Availability considers this aspect. Availability is the proportion of time that a plant component will be operating (or is in an operable condition).

Availability is operating time plus standby time. Availability factor (%) is-

If a pump is out of action (unavailable) for 400 hours in a 2000 hour period:

Availability factor is or 80%.

Availability actually consists of two components: reliability and the time taken to repair. Thus, poor reliability can sometimes be offset by improving the time needed to carry out repairs. This time period is called the Mean Time To Repair (MTTR) while the period of satisfactory failure-free operation is known as the Mean Time Between Failures (MTBF). The relationship between these parameters is expressed mathematically as

Availability =

This simplified mathematical expression assumes the MTTR is the same as Mean Time to Restore System as this will generally be the case. In some instances, time to restore system is more appropriate as there may be other non-system related delays e.g. time to attend the site. Table E4 presents a range of availabilities and the corresponding non-availabilities for a plant running 24 hours a day throughout the year. If a system has a MTBF of 400 years and a MTTR of 2 hours then the availability will be 99.9999%. Expressed in other terms, the plant will not be available for 0.3 minutes per year. A system having a MTBF of 2 years and a MTTR of 5 hours will have an availability of 99.97%: it will be non-available for 150 minutes per year.

Reliability engineering is an essential feature of work in industries such as aerospace, but its principles are still applicable to commercial HVAC&R applications, particularly as unreliable plant may have serious consequences in lost rent, lost productivity or increased overheads and maintenance costs.

Various manufacturers of major equipment items such as chillers, boilers, pumps, cooling towers and the like are able to supply historical data on reliability and downtime. This information is needed by them in assessing the cost of warranty claims.

Table E4 Numerical examples of availability

Appendix F - Glossary of terms

For the purpose of this Application Manual, the following terminology is used:

As-installed drawings – Detailed technical drawings showing the HVAC&R systems as they have been installed within the building.

Asset – Any item, entity or thing that has potential or actual value to an organisation. In the context of this document this relates to HVAC equipment or Infrastructure.

Asset management – The systematic planning and control of an asset throughout its life.

Asset register – A record of all systems and components including unique identifiers and plant information.

Benchmark – A reference point or metric against which a process, performance and/or level of quality can be measured

Benchmarking – The process of measuring and documenting performance and comparing the results internally or eternally.

Best Practice – A documented method, protocol, standard of delivery, industry guideline or Service Level developed and established by the market or community (consisting of Suppliers, Service Providers and End Users working together), which produce results that are superior to those obtained by other means.

Breakdown maintenance - Those unplanned activities, including adjustment and repair, which are necessary to restore an item of equipment or a system after failure of performance.

Business Case – A document that summarises the scope, benefits, costs and risks of a proposed solution to a business Need.

Check – Ascertain that the relevant item, quantity or level is in a normal or satisfactory condition. Make necessary adjustments and report if further work is required.

Commissionability – The extent to which the design and installation of HVAC&R systems facilitates system balancing and tuning to required performance.

Commitment – a contract or agreements with service providers, whether oral or in writing, for the provision of Facilities Services to the Demand Organisation at a specified value.

Competence – Ability to apply knowledge and skills to achieve the intended results

Compliance – The adherence to Standards, legislation, regulations or other requirements

Condition based maintenance – Maintenance strategy involving monitoring of selected parameters which are indicative of plant condition. Preventative maintenance is then carried out based on the data collected during routing or continuous monitoring.

Continuous Improvement – The recurring enhancement of performance

Corrective Action – Action to eliminate the cause of a Nonconformity and to prevent reoccurrence

Defects liability period – The period following completion and handover of the system or building during which the installer will be liable for defects in their work.

Demand – A stated requirement for a Service or Product to be delivered.

Demand Organisation – The entity (an organisation, functional unit of an organisation or authorised representative within an organisation) which has a Need and have the authority to incur costs to have its Requirements met; that acts as the intermediary between the Core Business and Support Services. In the context of this document it can be inferred to be the customer and is used interchangeably with the term Client in this document.

Due Diligence – The compilation, comprehensive appraisal and validation of information of an organisation required for assessing accuracy, commercial/ethical/social integrity, financial stability and functional competence. A system of behaviour that identifies relevant standards, legislation and by-laws that apply, monitors compliance, reports the results of compliance on a regular basis, rectifies any shortfalls in standards or any failure to comply, reviews all records on a regular basis to ensure they are current and accurate, and reviews all risk factors that apply to the property to ensure they are under control.

Economic life – The total length of time that equipment is expected to remain actively in service before it is expected that it would be cheaper to replace rather than maintain it.

End User – The individual person or organisation which uses the goods or services from a Service Provider or Supplier.

Equipment –  Any engineering plant, machine or component.

Essential Services - The plant and equipment, form of construction or fire safety strategy that is, or is proposed to be, implemented in a building to ensure the safety of persons using the building in the event of fire.

Facilities Management (FM) – The organisational function which integrates people, place and process within the Built Environment with the purpose of improving the quality or the life of people and the productivity of the Core Business.

Strategic Level – The level at which the objectives, policies and plans are defined and the assessment of how these goals are to be achieved

Tactical Level – The level at which Planning occurs to deliver the Strategy with relation to the management or specific mechanisms or resources

Operational Level – The level at which actions, activities or tasks are performed in a routine way that support the organisation and deliver the Tactical plan

Facilities Service – Support provision to the primary activities of an organisation, delivered by an internal or external provider. In the context of this document this relates to the provision of HVAC related services, maintenance, advice etc. Facilities Service in this context is distinct from Facilities Management due to the integrative function in the definition of Facilities Management

Facility – A collection of Assets which is built, installed or established to serve an entity’s Needs.

Good Practice – A method, protocol, standard of delivery or Service Level that exercises a degree of care, skill and diligence to meet the intended purpose, can be replicated and may also be scalable, so it can therefore be recommended to others. Distinguishable from Best Practice in that there are alternative methods that demonstrate superior results to Good Practice methods.

Hazard – The potential to cause injury or illness, or damage to property or environment. The term only describes the potential situation, not how likely it is that the dangerous event will occur.

HVAC&R – Heating, ventilation, air conditioning and refrigeration.

Infrastructure – The collection of facilities, equipment and services needed for the operation of an organisation.

Inspect – Determine the condition of equipment.

Internal / In-house Service Provision – Delivery and management of a Service by staff employed by the Demand Organisation

Key Performance Indicator (KPI) – A measure that provides essential information about performance of a Service, Requirement, task or duty.

Life-Cycle Cost – The total costs (in present value terms) expected to be spent on an asset during its operational existence.

Lifecycle Replacement Budget – Budget costs based on the replacement of key Asset or Infrastructure based on a predetermined interval depending on Asset / Infrastructure class. Includes but is not limited to electrical, HVAC, fire, vertical transport, architectural, civil, structural and hydraulic services.

Lubricate – Apply the lubricant recommended by the manufacturer.

Maintainability – The ease with which maintenance activities can be carried out on a system or component. One measure of maintainability is the Mean Time To Repair.

Maintenance – Technical, administrative, managerial and supervisory activities that are carried out on plant and equipment in order to retain performance and provide assurance that a system will work as and when required.

Maintenance costs – Materials and labour financial costs associated with maintaining the plant.

Maintenance management –  The organisation and implementation of maintenance within a defined maintenance policy.

Maintenance schedule – A list of planned maintenance tasks to be carried out during a given time period.

Maintenance strategy – Different types of maintenance approaches that can be applied to plant and systems. Scheduled maintenance, condition monitoring and reliability centered maintenance are all examples of differing maintenance strategies.

Maintenance policy – The system owners’ long-term plan for operation and maintenance of an asset within the constraints of the owners maintenance objectives and not withstanding any legislative requirements.

Method Statement – A document in which the Service Provider translates the demands, Requirements set out in the Specification into a delivery plan with resources, allocations and methodologies.

NCC – The National Construction Code of Australia as produced by the Australian Building Codes Board.

Nonconformity – Non-fulfilment of a Requirement

Occupant – person that inhabits a building that may be serviced by a HVAC&R system.

Operate – Start/stop, observe, record, report.

Operating costs – Those that keep the facility running after it has been put into service, including fuel, supplies, insurance, waste disposal, and associated salaries.

Owner – the person or business that has legal ownership of a HVAC&R system or building that includes a HVAC&R system.  The entity that has ultimate financial control over an asset and may be described as the Demand Organisation or Client.

Performance – a measurable characteristic of a system.

Planning – The process of aligning both short term and long-term goals and targets into planning documentation to ensure that all Requirements are carried out to the appropriate standards.

Repair – Rework existing element to serviceable condition, fit replacement part or assembly and report.

Requirement – A Need that is explicitly stated, generally implied (i.e. is a custom or common practice) or obligatory. Generally, Requirements are stated in any relevant documentation

Retrofit – Fit new component to modify existing installation to change performance (fuel consumption or labour intensity) to reduce outgoings or to suit new use.

Risk – The probability and consequences of occurrences of injury or illness, or damage to property or environment. More generally, risk is the probability and consequences of events or activities impeding the achievement of organisational objectives.

Routine maintenance – Equipment maintenance performed during normal working hours and on a regular time schedule basis.

Safe – Acceptable risk.

Safety measures maintenance – The maintenance required by legislation of the safety measures required by the NCC.

Scheduled maintenance – Those activities that should be carried out at predetermined intervals (planned) in accordance with an established schedule, to reduce the likelihood of the installation not meeting the required operating condition.

Service – Inspect, clean, adjust, top up (coolant, lubricant, water treatment), report.

Service Level – A complete description of Requirements of a Product, Process or System with their characteristics.

Service Level Agreement (SLA) – A document which has been agreed between the Demand Organisation and a Service Provider on performance, measurement and conditions of Service delivery

Service life – Period of time (years) during which a particular system or component remains in its original service application.

Service Provider – An organisation that delivers one or more Facilities Services to the Demand Organisation. Can be internal or external to the Demand Organisation.

Specification – The detailed description of the essential performance and / or technical Requirements for Services or Products and process set out by the Demand Organisation to make clear to the Service Provider the requirements to be fulfilled. The documentation that interfaces the Demand Organisation’s Needs with the Service Provider’s activities.

Stakeholder – A individual or organisation that can affect, or be affect by, or perceive itself to be affected by, a decision or activity.

Standard – External accredited criteria or expectations for the delivery of the activity including any relevant legislation.

Sustainability – Relates to the state of the Global system, including environmental, social and economic aspects (the interacting and interdependent 3 dimensions of sustainability), in which the Needs of the present are met without compromising the Needs of the future.

System – An arrangement of equipment, connected, associated or independent so as to form a complex unity.

System tuning – Local adjustment of a system where operation or testing has shown a fault or inefficiency including the re-assessment of control set points.

Tenant – person or business that leases all or part of a building from the owner.  In commercial property the tenant is the business that takes out a lease.  A tenant business comprises employees that may be Occupants of a building and subject to the performance of the HVAC&R system.

Volume – The total output of a measurable activity (e.g. Facilities Service) over a period of time.

Whole life costing – The continuous process of forecasting, recording and managing costs throughout the life of the equipment with the aim of minimising total long-term costs.

Workplace – They physical location where work is performed.

Work Station – A location containing furniture and supporting equipment (including telephony, IT and power connections) specifically designed or suitable for work-related activities and is suitable for permanent use.

Zero-based Budget – A fact-based budget preparation methodology that uses detailed asset lists, engineering and performance standards to assess resourcing needs with reference to benchmark / market unit costs to create a budget that does not reference previous expenditure levels but is based on tangible justifications for expenditure. All expenses need to be assessed and approved for the budget period, regardless of whether the budget is higher or lower than the previous one.

Appendix G – Referenced documents

This Application Manual should be read in conjunction with the relevant standards, codes and legislation applicable to the equipment and systems involved in the provision of heating, ventilating, air conditioning and refrigeration services.

Consideration should also be given to the specific requirements of the client/owner of the building or plant and any statutory requirements covering the location in which the plant has been installed.

Special note should be taken of the health, safety and energy efficiency requirements of the legislation in the State or Territory in which the plant is installed.

The following AIRAH Application Manuals have been referred to in this manual

Application Manual DA15       Filters

Application Manual DA17       Cooling Towers

Application Manual DA18       Water Treatment

Application Manual DA26       Indoor Air Quality

Australian and New Zealand Refrigerant handling code of practice Part 2: Systems other than self-contained low charge systems.

The following standards have been referred to in this manual

AS/NZS ISO 817         Refrigerants - Designation and safety classification

AS1055                       Acoustics - Description and measurement of environmental noise - General procedures

AS 1319                      Safety signs for the occupational environment

AS 1345                      Identification of the contents of pipes, conduits and fittings

AS 1470                      Health and safety at work - Principles and practices

AS 1668                      The Use of Mechanical Ventilation and Air Conditioning in Buildings.

AS 1668.1                   Fire and smoke control in multi compartment buildings

AS 1668.2                   Mechanical ventilation for acceptable indoor air quality.

AS 1851                      Maintenance of fire protection systems and equipment

AS/NZS 1892.1           Portable ladders Metal and reinforced plastic

AS 2107                      Acoustics - Recommended design sound levels and reverberation times for building interiors

AS 2436                      Guide to noise control on construction, maintenance and demolition sites

AS/NZS 2865              Safe working in a confined space

AS 2845.3                   Water supply - Backflow prevention devices - Field testing and maintenance 

AS/NZS 3000              Electrical installations - (Known as the Australia/New Zealand Wiring rules)

AS/NZS 3017              Electrical installations – Testing and inspection guidelines.

AS/NZS 3500              Plumbing and drainage

AS/NZS 3500.1.          Water services

AS/NZS 3500.1.2        Acceptable solutions

AS/NZS 3500.4           Hot water supply systems

AS/NZS 3500.4.2        Acceptable solutions

AS/NZS 3598.1           Energy audits Part 1: Commercial buildings

AS/NZS 3598.2           Energy audits Part 2: Industrial and related activities

AS 3653                      Boilers - Safety, management, combustion and other ancillary equipment

AS/NZS 3666              Air-handling and water systems of buildings – Microbial control.

AS/NZS 3666.1           Design, installation and commissioning

AS/NZS 3666.2           Operation and maintenance

AS/NZS 3666.3           Performance based maintenance of cooling water systems

AS/NZS 3666.4           Performance-based maintenance of air-handling systems (ducts and components)

AS 3788                      Pressure equipment – In service inspection

AS 3873                      Pressure equipment - Operation & Maintenance.

AS 4041                      Pressure piping

AS 4254                      Ductwork for air-handling systems in buildings.

AS 4426                      Thermal insulation of pipework, ductwork and equipment - Selection, installation and finish

AS/NZS 4536              Life cycle costing - An application guide

AS/NZS 4801              Occupational health and safety management systems - Specification with guidance for use

AS/NZS 5149              Refrigerating systems and heat pumps - Safety and environmental requirements

AS5667                       Water quality sampling

AS5667.7                    Guidance on the sampling of water and steam in boiler plants

AS5059                       Power station cooling water systems – Management of legionnaires’ disease health risk

AS/NZS 31000            Risk management - Principles and guidelines

END OF DOCUMENT